The interaction of nitrogen with titanium studied by soft X-ray absorption spectroscopy: adsorption versus implantation

Abstract

The interaction of nitrogen with titanium has been studied by means of N 1s X-ray absorption spectroscopy (XAS). It is shown that N 1s XAS spectra provide useful chemical information on this system. The spectra of nitrogen adsorbed on Ti indicate strong Ti3dN2p and Ti4SPN2p interactions. The Ti3d states are split by crystal field effects and are strongly hybridized to N2p orbitais. In comparison with a N 1s XAS spectrum from a reference TiN sample the spectra indicate a clear chemical similarity between the nitrogen chemisorbed layer on Ti and TiN bulk. In the case of the spectra of N + implanted in Ti, similar features to the above, at low primary beam energies (250 eV), are observed whereas at higher energies (above 1 keV) the spectra show a sharp quasi-atomic absorption peak which is attributed to weakly bonded N atoms in the bulk. The spectra also reflect disorder in the implanted layer and the two-dimensional character of the chemisorbed layer.