LEEIXS and XPS studies of reactive unbalanced magnetron sputtered chromium oxynitride thin films with air

Chromium oxynitride thin films were deposited onto polished carbon substrates by an unbalanced magnetron sputtering in a reactive atmosphere of argon and air with different relative humidities (concentrations of water vapor). The composition and thickness of chromium oxynitride thin films were measured by ion beam techniques such as: Rutherford backscattering spectroscopy (RBS) and resonant nuclear reaction analysis (RNRA). The nitrogen and hydrogen profiles were determined by RNRA and Tof-SIMS, the chemical bond analysis was carried out by low energy electron induced X-ray spectroscopy (LEEIXS) and X-ray photoemission spectroscopy (XPS). The LEEIX spectroscopic studies analysis have shown that, during metallic sputtering mode, the composition of Cr---N---O can be fitted only by Cr2O3 with low content of CrN and CrO2, and in the compound sputtering mode the CrO2 stoichiometry predominates in the presence of low content of CrN. XPS results have also indicated the existence of another compound with (CrO2)3'N stoichiometry.