Chemical effects correlated to nitrogen content of iron nitride films observed in the Fe L-shell X-rays induced by 5-keV electrons

Iron nitride thin films, produced by reactive magnetron sputtering, were characterized with grazing incidence X-ray diffraction, X-ray reflectometry, Rutherford backscattering spectrometry (RBS) and conversion electron Mössbauer spectroscopy. Their characteristic L-X-rays spectra, obtained with an electron microprobe analyzer equipped with a wavelength dispersive spectrometer, were compared to the spectrum of an iron standard. The spectra from the nitrides presented several chemical effects: change in the relative peak areas and shifts of the positions of the Lα1,2 and the Lβ1 peaks (chemical shift). The change in relative peak areas, namely the ratio between the Lβ1 and the Lα1,2 peaks, correlated well with the nitrogen content measured with RBS.