Development of Site Specific Cryogenic Specimen Preparation and Transfer of Frozen Liquids for Complementary High-Resolution Analysis by Scanning Transmission Electron Microscopy and Atom Probe Tomography
Development of Site Specific Cryogenic Specimen Preparation and Transfer of Frozen Liquids for Complementary High-Resolution Analysis by Scanning Transmission Electron Microscopy and Atom Probe Tomography
复制标题
通过扫描透射电子显微镜和原子探针断层扫描进行补充高分辨率分析的现场特定低温样品制备和冷冻液体转移的开发
DOI：
10.1093/micmic/ozad067.876
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发表时间：
2023
影响因子：
2.8
通讯作者：
Douglas J
中科院分区：
文献类型：
--
作者：
Douglas J
对固液界面的高分辨率分析，例如电池材料中的电解质/电极，一直有相当大的兴趣。通过在样品制备之前使用冷冻系统，从而保护天然环境，将极大地促进此类分析[1]。在涉及锂等轻元素的系统上进行复杂的3D纳米级微结构分析对于扫描透射电子显微镜（STEM）和原子探针断层扫描（APT）来说都是独立的挑战，它们的组合对于获得对结构和成分的必要洞察是必要的。APT需要高纵横比的针状样本，其顶点直径通常小于100 nm，感兴趣的区域足够接近顶点，使得其将包含在50 nm x 50 nm x 80 nm的典型分析体积内。因此，APT样品在STEM可实现的电压下是电子透明的，因此适合STEM成像和基于光谱的分析，尽管弯曲尖端几何形状的非均匀厚度可能会带来挑战。STEM与APT分析的互补性已经在许多材料系统中得到展示，现在在许多机构中相对常见[2]。用于补充STEM分析的APT样品可以由电抛光的散装针（在适当的金属/合金的情况下）形成，或者更常见的是通过聚焦离子束（FIB）顶出放置在金属针和TEM半网格的暴露的最顶部部分上。STEM合适的保持器和APT合适的保持器之间的转移在大多数情况下仍然是手动过程，并且即使在环境条件下通过机械处理的产量损失也可能是一个重大问题。
There has been considerable interest in the high-resolution analysis of solid-liquid interfaces, for instance, electrolyte/electrode within battery materials. Such analyses would be greatly facilitated through the use of freezing the system prior to sample preparation and thus preserving the native environment [1]. Carrying out analysis of complex 3D nanoscale microstructures on systems involving light elements such as lithium can be independently challenging for both scanning transmission electron microscopy (STEM) and atom probe tomography (APT), where their combination is necessary to gain the necessary insights into structure and composition. APT requires high aspect ratio, needle shaped specimens with an apex diameter generally less than 100 nm, with the region of interest sufficiently close to the apex that it will be contained within a typical analysed volume of 50 nm x 50 nm x 80 nm. As such, APT specimens are electron transparent at STEM achievable voltages and hence suitable for STEM imaging and spectroscopy-based analysis, although there can be challenges with non-uniform thicknesses from curved tip geometries.The complementarity of STEM followed by APT analyses has been showcased on a number of material systems and is now relatively common across many institutions [2]. APT samples that are intended for complementary STEM analysis can be formed from electropolished bulk needles in the case of appropriate metals/alloys or more commonly placed by focused-ion beam (FIB) liftout onto metal needles and the exposed topmost sections of TEM half grids. The transfer between STEM suitable holders and APT suitable holders is still, for the most part, a manual process and yield loss through mechanical handling even under ambient conditions can be a significant issue.