*Burkhard Zimmermann, Goesta Mattausch, Fred Fietzke, Bert Scheffel, Jens-Peter Heinß, Michiel Top, Christoph Metzner, Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, Dresden, Germany
Highly productive substrate pre-treatment, coating, and post-treatment methods are required to combine versatile and environmentally-friendly physical vapor deposition (PVD) processes in vacuum with economic demands. Electron beam (EB) technologies are very promising to address these requirements. This talk gives an overview of various types of electron sources which are in use at FEP for different steps along the process chains in thin-film technology, and which are based on the generation of free electrons by gas discharges.
Compact low-voltage electron beam (LVEB) sources based on hollow-cathode arc discharges have proven their value in diverse applications, mostly in plasma activation of high-rate PVD. The latest generation of these plasma sources with magnetic enhancement allows for creating high-power plasmas with high and smoothly distributed ion densities in large volumes. This, for example, enables high etching rates during sputter cleaning of substrates as highly efficient and fast inline pre-treatment prior to coating. Furthermore, new high-rate deposition methods as, e.g., the hollow-cathode arc PECVD of carbon or silica-based coatings, and also advanced process control techniques based on the optical emission of the hollow cathode discharge could be developed.
High-voltage glow-discharge EB sources with cold cathodes have previously been reported to provide an economically attractive alternative to conventional thermionic electron beam guns. In this paper, a new type of a discharge-based EB source with “hybrid cathode” will be discussed. It combines the simplicity of cold-cathode devices with beneficial performance parameters reached so far with traditional thermionic electron sources only. This regards, for instance, the higher power density in the focal spot and the higher acceleration voltage.