ABSTRACT
Tungsten-based thin films have been developed as an alternative to traditional coating systems for many various applications. Sputterdeposited films have found their usage as diffusion barriers in microelectronics [1], semiconductor devices [2], interconnect technology [3], and also in the field of hard coatings for mechanical applications [4]. Although tungsten-based thin films generally exhibit excellent mechanical properties, their performance as protective coatings is markedly limited due to relatively low thermal stability and oxidation resistance of this system at high temperatures. Coatings for mechanical applications, such as cutting and forming applications or machining operations, however, perform typically under extreme conditions. Besides high hardness and resistance to fracture toughness, it also requires high thermochemical stability. An improvement of oxidation behavior and wear resistance of tungsten-based films in tooling applications has gained interest of many researchers. In last decade, many works have been devoted to investigations of the influence of the addition of various elements into these films on their physical and mechanical properties [5,6]. The main motivation of all the studies was to improve the performance of tungsten-based films in aggressive environments without changes of the mechanical properties reached during their development [7].
