Mapping interfacial excess in atom probe data

Using modern wide-angle atom probes, it is possible to acquire atomic scale 3D data containing 1000 s of nm² of interfaces. It is therefore possible to probe the distribution of segregated species across these interfaces. Here, we present techniques that allow the production of models for interfacial excess (IE) mapping and discuss the underlying considerations and sampling statistics. We also show, how the same principles can be used to achieve thickness mapping of thin films. We demonstrate the effectiveness on example applications, including the analysis of segregation to a phase boundary in stainless steel, segregation to a metal–ceramic interface and the assessment of thickness variations of the gate oxide in a fin-FET. - Highlights: • Using computational geometry, interfacial excess can be mapped for various features in APT. • Suitable analysis models can be created by combining manual modelling and mesh generation algorithms. • Thin film thickness can be mapped with high accuracy using this technique.