XPS characterization of the composition and bonding states of elements in CN layers prepared by ion beam assisted deposition x

CN layers were gr own on polished Si (100 )wafers by the ion beam assisted deposition (IBAD technique at temperatures varying between 200 and 600°C . A Kaufman type ion source fed by Ar and N₂ was applied together with an e-beam heated evaporation source of graphite for the deposition of the CN layers.The composition and chemical bonding state of elements were studied by X-rayphotoelectron spectroscopy.The N-content varied in the range of 8 –16 at.% and showed a decrease with the increase of deposition temperature.The broad C1s and N1s XPS lines manifested several bonding states.The elative intensities of the component peaks varied with the preparation conditions.The two main components of the N1s peak situated at BE s 398.2 eV and 400.6 eV were assigned to sp² (C –N =C )and sp³ (N –C )type bonding states,espectively.The stability of the sp³ states was higher than that of the sp² ones, because the intensityof the 398.2 eV component decreased preferentially with increasing deposition temperature.A post-deposition treatment with low energy ion beam resulted in a significant increase in N₂ ⁺ the overall N-content on the surface,with a preferential increase in the concentration of sp² type nitrogen.