Powder metallurgic fabricated plug targets for the synthesis of AlCrSiWN multicomponent coating systems

Abstract

Monolithic and alloyed targets, conventionally produced by means of melt metallurgy, have been established as conventional target material designs for physical vapor depositions (PVD). However, integrating refractory metals into the sputtering material, leads to restrictions concerning the solubility and phase formation in the target compound. In this context, plug targets are commonly used to deposit multinary coatings with a desired chemical composition. However, producing plugs by means of melt metallurgy restricts the types and amounts of integrated elements.Since current PVD coating concepts aim at an extension of the functionality spectrum by element doping, new target concepts are required. The use of several monolithic targets is one method to produce coatings combining various elements within one coating. Yet depending on the target setup, this approach can result in a nanolaminar coating deposition. To circumvent this, a new production route, which ensures the integration of sintered CrSiW plugs in a monolithic aluminum target, is examined in this study. Two coating deposititons, each with an Al(CrSiW)20 and an Al(CrSiW)48 plug target, were performed by means of direct current (DC) magnetron sputtering and compared with a reference coating, which was synthesized using an AlCr20 target. The dense morphology of AlCrN was significantly changed to a more columnar structure due to slight additions of silicon and tungsten. High aluminum contents in AlCrN and AlCrSiWN, in turn, resulted in a distinct enhancement of the mechanical properties.