Design and construction of an acetylene capable PVD based deposition system ; Konstruktion und Aufbau einer Acetylen-fähigen PVD Beschichtungsanlage

Abweichender Titel nach Übersetzung der Verfasserin/des Verfassers ; In the field of hard materials, and especially hard coatings, are carbon-based compounds one of the most important and prevalent material class being still topic of diverse research activities. Since the discovery and commercialization of cemented carbides in the early 1920’s – e.g. the alloy WIDIA (in German: “Wie Diamant”) implying the term diamond like – the variety of carbon-based alloys and coating materials increased vastly. The properties that come close to those of diamonds have inspired scientists and engineers worldwide for decades. In particular, the synthesis of diamond-like carbon (DLC) coatings using the full variety of physical vapor deposition techniques is still an ongoing challenge. The impressive track record of DLC based coatings, is not only related to the unique tribo-mechanical properties – hardness between 60 to 80 GPa (highly pure diamonds obtain 100 GPa or even higher) combined with coefficient of frictions (COF) below 0.05 – but also to the well-described characterization and synthesis methods. Especially, the broad range of bonding states, e.g. tetrahedral amorphous carbon (ta-C) or amorphous carbon with or without metal constituents (a-C or a-C:Me), accessible by sputtering is a key-factor of this deposition technique. Nevertheless, the application of reactive gases – such as acetylene (C2H2) – during sputter deposition also implies the introduction of hydrogen and hence a drastic change of the coating properties – especially, reduced hardness for ta:C:H based coatings. Recent studies highlighted that a pronounced ionization of acetylene during sputtering results in a larger proportion of sp3 hybridized carbon and hence increased hardness values. High Power Impulse Magnetron Sputtering (HiPIMS) is one possibility to control the ionization state of metal but also non-metal species during reactive sputter deposition. However, these processes have not yet been fully described by academia as well as industrial ...