Stender Patrick, Heil Tobias, Kohl Helmut, Schmitz Guido
Institut für Materialphysik, Universität Münster, Wilhelm-Klemm Str. 10, 48149 Münster, Germany.
Ultramicroscopy. 2009 Apr;109(5):612-8. doi: 10.1016/j.ultramic.2008.12.009. Epub 2008 Dec 24.
Whereas transmission electron microscopy (TEM) is a well established method for the analysis of thin film structures down to the sub-nanometer scale, atom probe tomography (APT) is less known in the microscopy community. In the present work, local chemical analysis of sputtered Fe/Cr multilayer structures was performed with energy-filtering transmission electron microscopy (EFTEM) and APT. The single-layer thickness was varied from 1 to 6nm in order to quantify spatial resolution and chemical sensitivity. While both the methods are able to resolve the layer structure, even at 2nm thickness, it is demonstrated that the spatial resolution of the APT is about a factor of two, higher in comparison with the unprocessed EFTEM data. By calculating the influence of the instrumental parameters on EFTEM images of model structures, remaining interface roughness is indicated to be the most important factor that limits the practical resolution of analytical TEM.
虽然透射电子显微镜（TEM）是一种成熟的用于分析低至亚纳米尺度薄膜结构的方法，但原子探针断层扫描（APT）在显微镜学界的知名度较低。在本工作中，利用能量过滤透射电子显微镜（EFTEM）和APT对溅射的Fe/Cr多层结构进行了局部化学分析。为了量化空间分辨率和化学灵敏度，将单层厚度从1nm变化到6nm。虽然这两种方法都能够分辨层结构，即使在2nm厚度时也是如此，但结果表明，APT的空间分辨率比未处理的EFTEM数据高约两倍。通过计算仪器参数对模型结构EFTEM图像的影响，表明剩余的界面粗糙度是限制分析型TEM实际分辨率的最重要因素。
