Exploring the Potential of High Power Impulse Magnetron Sputtering for Tailoring the Chemical Composition and the Properties in Metal Oxynitride Films

Metal oxynitrides (MONs) are a new class of functional materials in which tuning of the O-to-N ratio in the non-metal sublattice enables to tailor their properties between those of the reference metal oxide and the metal nitride systems. In thin film form MONs are frequently deposited by reactive magnetron sputtering techniques under the presence of two reactive gases (O₂ and N₂). In this case the ability to control the Oto- N ratio in the growing MON films is largely determined by the stability of the reactive sputtering process in the transition zone between metallic and compound target. Recently it has been shown that the implementation of a newly developed highly ionized magnetron sputtering technique, i.e., the high power impulse magnetron sputtering (HiPIMS), can also allow for a stable operation during reactive deposition of metal oxides. In this chapter the state of the art regarding the process characteristics in reactive HiPIMS processes are reviewed and the potential of HiPIMS for tailoring the composition and the properties of MON films is discussed.

Keywords: Material science, thin films, coatings, PVD, ionized-PVD, magnetron sputtering, HiPIMS, HPPMS, reactive sputtering, process stability, transition zone, metal oxides, metal nitrides, metal oxynitrides, chemical composition, functional properties.