continuous increase of the reactive gas (higher than 14 sccm),
there is another structure change, zone II. This structural change is
well correlated with the evolution of the oxygen and nitrogen
content of the coatings (Table 1). The semi-transparent sample,
deposited with 15 sccm, shows a significant increase of the
oxygen content along with a significant decrease of the nitrogen
and its stoichiometry could correspond to an oxynitride-type
structure. However, the exact determination of the crystalline
structure is again very difficult due the reduced number of visible
diffraction peaks. Nevertheless, and according to very few research
studies [19–22] the diffraction peaks located at 2θ≈21.1°,
2θ≈30° and 2θ≈32.9° could correspond to a bcc γ-Zr2ON2-
type structure (ICDD card n° 48-1635) [23].