Interdisciplinary Centre for Electron Microscopy, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.
Electron Spectrometry and Microscopy Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.
Sci Rep. 2017 Sep 6;7(1):10630. doi: 10.1038/s41598-017-07537-6.
The ability to obtain three-dimensional (3-D) information about morphologies of nanostructures elucidates many interesting properties of materials in both physical and biological sciences. Here we demonstrate a novel method in scanning transmission electron microscopy (STEM) that gives a fast and reliable assessment of the 3-D configuration of curvilinear nanostructures, all without needing to tilt the sample through an arc. Using one-dimensional crystalline defects known as dislocations as a prototypical example of a complex curvilinear object, we demonstrate their 3-D reconstruction two orders of magnitude faster than by standard tilt-arc TEM tomographic techniques, from data recorded by selecting different ray paths of the convergent STEM probe. Due to its speed and immunity to problems associated with a tilt arc, the tilt-less 3-D imaging offers important advantages for investigations of radiation-sensitive, polycrystalline, or magnetic materials. Further, by using a segmented detector, the total electron dose is reduced to a single STEM raster scan acquisition; our tilt-less approach will therefore open new avenues for real-time 3-D electron imaging of dynamic processes.
获得关于纳米结构形态的三维（3-D）信息的能力阐明了物理和生物科学中许多材料的有趣性质。在这里，我们展示了扫描透射电子显微镜（STEM）中的一种新方法，该方法可快速可靠地评估曲线型纳米结构的 3-D 结构，而无需通过弧形对样品进行倾斜。我们使用一维晶体缺陷（称为位错）作为复杂曲线物体的典型示例，展示了通过选择会聚 STEM 探针的不同射线路径记录的数据，其 3-D 重建速度比标准倾斜弧形 TEM 层析技术快两个数量级。由于其速度和对与倾斜弧形相关的问题的免疫性，无倾斜 3-D 成像为研究辐射敏感、多晶或磁性材料提供了重要优势。此外，通过使用分段探测器，总电子剂量降低到单个 STEM 光栅扫描采集；因此，我们的无倾斜方法将为实时 3-D 电子动态过程成像开辟新途径。
