Analysis of Thin Surface Layers by Fe-57 Mössbauer Backscattering Spectrometry

Abstract

Fe-57 Mössbauer spectra for extremely thin surface layers (600–3000 Å) were obtained by detecting internal conversion electrons emitted after resonant absorption. The sample was placed inside a proportional counter specifically designed for Mössbauer backscattering measurements. Helium-10% methane flowgas was used to detect the conversion electrons. It is estimated from the observed spectra that this technique can be used to obtain Mössbauer backscattering spectra for iron-containing surface layers 50–3000-Å thick. Backscattering spectra for thicker surface layers (0.2–0.5 mil) were obtained by merely changing to an argon-10% methane flow-gas mixture and counting the 6.3-keV internal conversion x rays rather than conversion electrons.

Local States of Iron in TiN/Fe Interface

“…This means that about 60% of the electrons emitted from the sample surface have originated within this layer. However, already in one of the first works on CEMS [5] it was shown that some resonant absorption could be seen even from 300 nm depth.…”

Advantages of Mössbauer polarimetric methods in material studies

“…Conversion electron Mössbauer spectroscopy (CEMS) was demonstrated already in 1970 [14]. Since that time observation of layers, thin layers and single atomic layers Fig.…”

Advantages of Mössbauer polarimetric methods in material studies

“…Conversion electron Mössbauer spectroscopy (CEMS) was demonstrated already in 1970 [14]. Since that time observation of layers, thin layers and single atomic layers In standard CEMS detectors, sample surface is perpendicular to the direction of gamma rays.…”