Marta Miranda Marti¹, Max Philip Möbius¹, Kirsten Bobzin¹, Peter Polcik², Szilard Kolozsvari², Matthias Pitzal^2
1RWTH Aachen University, Aachen, Germany
²Plansee Composite Materials GmbH, Lechbruck am See, Germany
The evaporation of ceramic materials via arc-PVD has shownextensive challenges due to the arc instability resulting in local overheating and crack formation. Various approaches for improving process stability include the addition of C or working in a N₂-reactive atmosphere. In this work, TiN and TiB₂ are combined into composite TiB/TiN powder-metallurgical targets and bonded by high temperature braizing to pure Mo and MoCu backplates. Arc stability is analyzed in terms of arc mobility employing various pulse parameters through in-situ visual inspection, process parameter analysis, e.g. target voltage, and plasma measurements by optical emission spectroscopy. The deposition processes are performed in argon and nitrogen atmospheres. Post-deposition, the target is visually inspected and analyzed for mass variation by means of a precision scale, groove depth employing a depth gauge, and surface topography. Stable arc operation is achieved under moderate pulse current parameters I_P > 100 A. Maximum arc stability is obtained using a pulsed arc with an extended pulse-off time t_off = 2.500 µs and a short pulse-on duration t_on = 75 µs. Furthermore, magnetic arc steering is ineffective in controlling arc trajectory, independent of the back plate composition. Minor nitrogen addition in the atmosphere improves arc stability and modifies target surface topography. In argon, the surface exhibits pronounced irregular radial cracks, whereas in the nitrogen-containing atmosphere, it becomes smoother and more homogeneous, and the target presents reduced mass loss. This study demonstrates that TiB/TiN targets can be used for arc deposition of TiBN coatings.