Substructure in the columnar crystals of the Ti0.45O0.20N0.35 oxynitride thin film

In situ oxygen doping modifies both the morphology and texture of the TiN films. It has been found that beyond 15 at% oxygen doping the columnar morphology is preserved however the <111> texture is changed to the <002>. The detailed structure analysis of the Ti0.45O0.20N0.35 oxynitride films prepared by reactive unbalanced magnetron sputtering (UBMS) in an argon/nitrogen/oxygen mixture atmosphere discovered a substructure in the bulk of the TiN(O) single crystal columns. In the cross sectional transmission electron microscopy (X-TEM) images the substructure is showing up in form of fibre-like morphology parallel to the axis of the columnar crystals and in a honeycomb-like supernetwork in the cross section of the single crystal columns in the plane view TEM specimens. The fibre-like substructure proceeds to the film surface and manifests itself in the morphology of the dome-shaped surface areas of the single crystal columns as revealed by atomic force microscopy analysis.

► Complex analysis of the bulk structure and surface morphology of Ti45O20N35 oxynitride film. ► Fibre-like substructure in the bulk of TiN(O) single crystal columns. ► Surface morphology features correspond both with the fibres and the columnar crystals.