Performance Evaluation of Deep,Near Ultraviolet Laser Assisted Atom Probes for a range of Material system

TL;DR

This study systematically compares the effects of near-ultraviolet and deep ultraviolet lasers on atom probe tomography across various materials, revealing improvements in data quality and material analysis capabilities.

Contribution

It provides a comprehensive evaluation of DUV laser effects on different material classes in atom probe tomography, which was previously unexplored.

Findings

DUV lasers improve data quality metrics

Thin coatings enhance data quality for both wavelengths

Material-specific responses to laser wavelengths identified

Abstract

Atom probe tomography (APT) enables near atomic scale three dimensional elemental mapping through the controlled field evaporation of surface atoms triggered by the combined application of a DC voltage and either voltage or laser pulses. As the selected laser wavelength for the atom probes transitioned from the near-infrared (1050 nm) to shorter wavelengths e.g., green (532 nm) and near ultraviolet, the quality of data improved and the range of materials amenable for analysis broadened. A new commercial laser atom probe with a wavelength of 257.5 nm, referred to as deep ultraviolet (DUV), has been recently launched. However, the effects of DUV lasers on different classes of materials have not yet been systematically investigated. In this study, a range of materials, including metals, semiconductor, and oxides, have been examined using commercial atom probes with different laser wavelengths but in principle comparable particle detection system. The quality of the NUV and DUV laser atom probe data is evaluated based on four key metrics: background, detection events, ion detection histogram, and mass-resolving power. Furthermore, the application of a thin coating to the finished APT specimens enhances the data quality for both laser wavelengths.