Jan-Peter Urbach, Thomas Schütte, PLASUS GmbH, Mering, Germany
Automated process control in plasma processing is indispensable to meet the ever increasing demands for better specifications and lower scrap rates. This requires short control loops, and in turn measurement systems that gather information about process conditions as well as product properties as close as possible to the manufacturing process.
Spectroscopic plasma process monitoring is a standard in-situ measurement technique to acquire data from the actual coating process. In addition spectroscopic reflectometry of the coated surface reveals simultaneously properties of the produced layer such as film thickness or color values. Furthermore the chemical film composition as well as the surface roughness influence the optical properties of the surface and can be detected in the photometric signal.
In this talk, examples of combined real-time measurements of in-situ plasma monitoring and in-situ reflectometry of the layer in demanding coating processes are presented, including applications in tribological and nanocrystalline coating. By combining information from both measurement techniques in a single system in real-time the accuracy of the process control and in turn the product quality are improved.