Quantitative aspects of ToF-SIMS analysis of metals and alloys in a UHV, O$_2$ and H$_2$ atmosphere

Ekar, Jernej (author), Kos, Saša (author), Kovač, Janez (author)

Although secondary ion mass spectrometry (SIMS) is a versatile method used in the fields of surface analysis, depth profiling and elemental and molecular mapping, it also lacks quantification capabilities. The main reason for this is the matrix effect, which influences the ionization yield of secondary ions with respect to the substrate from which the analyzed compounds originate. There are several approaches to reduce the matrix effect, and gas flooding is one of the easiest methods to apply. In this work, we have investigated the possibilities of the ToF-SIMS method for the quantification of selected metals and alloys containing these metals in different ratios by reducing the matrix effect in the presence of different atmospheres. The measurements were performed in the ultra-high vacuum (UHV) environment, H$_2$ and O$_2$ atmospheres. H$_2$ flooding shows the most significant improvements compared to the UHV analysis, while O$_2$ is also promising but has some limitations. Improvements are most evident for the transition metals Ti, Cr, Fe, Co and Ni employed in our study, while the p-block elements such as Al and Si do not change so extensively. The deviations from the true atomic ratios of selected transition metals in different alloys reach a maximum of only 46 % when analyzed in the H$_2$ atmosphere. In contrast, these values are 66 and 228 % for the O$_2$ atmosphere and UHV environment, respectively. Our results suggest that gas adsorption and consequent formation of a new matrix on the surface, especially in the case of hydrogen, reduces the differences between the different chemical environments and electronic structures of the surface. In this way, the quantitative aspects of the SIMS method can be improved.

• Language: English
• Keywords: ToF-SIMS quantification, H$_2$ and O$_2$ gas flooding, matrix effect reduction, cluster secondary ions
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: 11 str.
• Numbering: Vol. 49, art. 104408
• PID: 20.500.12556/RUL-156332
• UDC: 55
• ISSN on article: 2468-0230
• DOI: 10.1016/j.surfin.2024.104408
• COBISS.SI-ID: 194756611
• Publication date in RUL: 20.05.2024

Record is a part of a journal

• Title: Surfaces and interfaces
• Publisher: Elsevier
• ISSN: 2468-0230
• COBISS.SI-ID: 526516249

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: ToF-SIMS kvantifikacija, kovine, matrični efekt, preplavljanje, atmosferski plini