NITROGEN PROFILING IN NITRIDE FILMS AND NITROGEN-IMPLANTED SAMPLES USING THE N-14(ALPHA,ALPHA) AND N-14(ALPHA,P) REACTIONS AT 6 MEV INCIDENT ENERGY

We investigate the nitrogen profiling potentiality using incident alpha particles from 5 to 7 MeV. In this energy range the alpha scattering cross sections on light elements are substantially larger than the Rutherford cross sections and therefore lead to competitive sensitivity. Moreover, another advantage is the high mass resolution which allows to profile simultaneously carbon, nitrogen and oxygen. The analysis of TiN, NbTiN films and nitrogen implanted steel are presented. The inclusion, in the simulation program, of the N-14(alpha, alpha) and N-14(alpha, p) cross sections allows to get a complete reproduction of the spectra and authorizes to determine accurately the nitrogen profile. Such a dual nitrogen analysis improves profile determination in case of thick analyzed layers. The sensitivity limits connected to the alpha scattered yield on steel substrate are 10(16) and 5 x 10(16) N atoms/cm2 for the N-14(alpha, alpha) and N-14(alpha, p) reactions, respectively.