Ceguerra Anna V, Breen Andrew J, Cairney Julie M, Ringer Simon P, Gorman Brian P
Australian Centre for Microscopy & Microanalysis (ACMM), The University of Sydney, Sydney, NSW2006, Australia.
School of Aerospace, Mechanical and Mechatronic Engineering (AMME), The University of Sydney, Sydney, NSW2006, Australia.
Microsc Microanal. 2021 Feb;27(1):140-148. doi: 10.1017/S1431927620024873.
Current reconstruction methodologies for atom probe tomography (APT) contain serious geometric artifacts that are difficult to address due to their reliance on empirical factors to generate a reconstructed volume. To overcome this limitation, a reconstruction technique is demonstrated where the analyzed volume is instead defined by the specimen geometry and crystal structure as determined by transmission electron microscopy (TEM) and diffraction acquired before and after APT analysis. APT data are reconstructed using a bottom-up approach, where the post-APT TEM image is used to define the substrate upon which APT detection events are placed. Transmission electron diffraction enables the quantification of the relationship between atomic positions and the evaporated specimen volume. Using an example dataset of ZnMgO:Ga grown epitaxially on c-plane sapphire, a volume is reconstructed that has the correct geometry and atomic spacings in 3D. APT data are thus reconstructed in 3D without using empirical parameters for the reverse projection reconstruction algorithm.
当前用于原子探针断层扫描（APT）的重建方法存在严重的几何伪像，由于依赖经验因素来生成重建体积，这些伪像难以解决。为克服这一限制，展示了一种重建技术，其中分析体积由样品几何形状和晶体结构定义，该几何形状和晶体结构由透射电子显微镜（TEM）以及在APT分析前后获取的衍射确定。APT数据使用自下而上的方法进行重建，其中APT后的TEM图像用于定义放置APT检测事件的基底。透射电子衍射能够量化原子位置与蒸发样品体积之间的关系。使用在c面蓝宝石上外延生长的ZnMgO:Ga的示例数据集，重建了一个在三维空间中具有正确几何形状和原子间距的体积。因此，在不使用反向投影重建算法的经验参数的情况下，以三维方式重建了APT数据。
