The nitrogen implanted profiles in cobalt films that are generated by N2+ bombardment with three energies of 0.5, 2.0 and 5.0 keV are simulated by the analytical Schulz-Wittmaack expression and the SRIM program, respectively. Taking the both simulated profiles as concentration-depth profiles, the corresponding measured AES depth profiling data of implanted nitrogen are perfectly fitted by the Mixing-Roughness-Information depth (MRI) model.