Reflections on the projection of ions in atom probe tomography

TL;DR

This paper compares two projection methods in atom probe tomography, showing that the azimuthal equidistant projection offers greater robustness and potential accuracy over the traditional point-projection method.

Contribution

It provides a comparative analysis highlighting the advantages of the azimuthal equidistant projection for more reliable 3D reconstructions in atom probe tomography.

Findings

Azimuthal equidistant projection is more robust to parameter errors.

It potentially yields more accurate 3D reconstructions.

The study challenges the dominance of the point-projection method.

Abstract

There are two main projections used to transform, and reconstruct, field ion micrographs or atom probe tomography data into atomic coordinates at the specimen surface and, subsequently, in three-dimensions. In this article, we present a perspective on the strength of the azimuthal equidistant projection in comparison to the more widely used and well-established point-projection(or pseudo-stereographic projection), which underpins data reconstruction in most software packages currently in use across the community. After an overview of the reconstruction methodology, we demonstrate that the azimuthal equidistant is more robust with regards to errors on the parameters used to perform the reconstruction and is therefore more likely to yield more accurate tomographic reconstructions.