Thomas Schütte, Peter Neiß, Marius Radloff, Hokuto Kikuchi, PLASUS GmbH, Mering, Germany
HIPIMS processes and other pulsed plasma processes are becoming more and more popular for coating applications in industry and R&D. To exploit the full potential of HIPIMS processes for production and film development, continuous pulse-resolved measurements are essential to optimize the coating process in terms of deposition rate, film composition and morphology, as the composition of the plasma particles changes during the HIPIMS pulse.
So far, spectroscopic and electrical plasma monitoring and process control is available by means of pulse-averaging data acquisition only. Expensive high-end diagnostic equipment is capable to acquire pulse-resolved data, however, with the lack of continuous operation and real-time feedback control.
This presentation will introduce continuous spectroscopic and electrical pulse-resolved data acquisition with unprecedented time resolution and sampling rate in a multi-channel setup at reasonable expenses. The continuous monitoring of the temporal behavior of particle densities as well as voltage and current within the pulse width over the complete coating process allows a precise synchronization of substrate biasing, secondary target pulsing (kick pulsing/bipolar pulsing) and pulse power as well as optimization of reactive gas flow. This will enhance process stability and production quality in industrial application and provide R&D new opportunities to tailor coatings with advanced or new properties.
Examples of a HIPIMS process with metallic Ti and reactive TiO₂ and pulsed-DC applications with Al and AlN demonstrating the pulse-resolved and continuous data acquisition are presented.