Characterization of advanced coating architectures deposited by an arc-HiPIMS hybrid process

Abstract

We describe advanced coating architectures achieved by a novel combined vacuum arc evaporation/HiPIMS PVD-system which permits us to exploit the advantages of both processes. This system combines three highly ionized processes - arc evaporation, classical HiPIMS and Arc Enhanced Glow Discharge (AEGD). The process technology is commercially named HI3 (High Ionization Triple). The ion cleaning is based on the AEGD process. The tailoring of coating architectures is driven by the advantages of the individual techniques. Vacuum arc evaporation has limitations concerning the materials which can be evaporated, but is characterized by high process stability and high deposition rates, while sputter-deposition is implemented to provide a more complex composition and to achieve multilayer architectures with enhanced properties. Magnetron sputtering processes can be used to atomize materials which are difficult to evaporate by vacuum arc evaporation e.g. Si, SiC, WC, TiB2 and others. The high ionization of the HiPIMS process results in a dense coating structure even for nitride top coatings (e.g. VZrN). Both deposition methods can be run as individual process steps, and also in a hybrid mode. This hybrid process opens a window to generate multilayer as well as nanomultilayers down to sub-nanometer layers. Functional top layers with outstanding properties can be deposited in addition. Selected advanced coating architectures are highlighted. TiB2, SiBC and VZr targets were used to generate individual hybrid coating architectures in combination with arc deposited AlTiN coatings. Every coating started with an AlTiN base coating, followed by a hybrid coating and a HiPIMS top coating. Also classical arc coatings using AlTi and TiSiX cathodes were deposited and investigated to work out the differences to the hybrid coatings. TEM preparations were done for each coating type and investigation of nano beam diffraction were made for the top coating deposited by pure classical HiPIMS. Structural evolutions are discussed.