The effect of low-energy N-2(+) ion beam bombardment on InAs, InP, and InSb surfaces has been studied using in situ X-ray photoelectron spectroscopy. The formation of a nitrided surface layer has been observed for all investigated AIII-BV semiconductors. Beside the emerging In-N bonds also P-N bonds were detected for InP, whereas for InAs and InSb, there is no evidence for the formation of As-N and Sb-N bonds, respectively. An analysis of the N Is core level peak also reveals the build-in of interstitial nitrogen. A change of the ion beam incidence angle has great influence on the composition of the surface layer as demonstrated for InP. The amount of nitrogen in P-N bonds and of interstitial nitrogen decreases for changing the ion incidence to grazing angles. A detailed XPS analysis provides information on the temporal evolution of the process of nitridation and the thickness of the nitrided surface layer.