Exploring the Accuracy of Isotopic Analyses in Atom Probe Mass Spectrometry
Frederick Meisenkothen, Daniel V. Samarov, Irina Kalish, Eric B. Steel
Atom probe tomography (APT) can theoretically deliver accurate chemical and isotopic analyses at a high level of sensitivity, precision, and spatial resolution. However, empirical APT data often contain significant biases that lead to erroneous chemical concentration and isotopic abundance measurements. The present study explores the accuracy of quantitative isotopic analyses performed via atom probe mass spectrometry. A machine learning-based adaptive peak fitting algorithm was developed to provide a reproducible and mathematically defensible means to assign regions of interest in the mass spectrum to specific ion species. The isotopic abundance measurements made with the atom probe are compared directly with the known isotopic abundance values for each of the materials. Even in the presence of exceedingly high numbers of multi-hit detection events (up to 80%), and in absence of any deadtime corrections, isotopic abundance measurements were consistently measured with an accuracy better than 3% relative.
, Samarov, D.
, Kalish, I.
and Steel, E.
Exploring the Accuracy of Isotopic Analyses in Atom Probe Mass Spectrometry, Ultramicroscopy, [online], https://doi.org/10.1016/j.ultramic.2020.113018
(Accessed August 11, 2022)