Fraunhofer Institute for Material and Beam Technology IWS
Laser-Arc Technology
IWS engineers developed the Laser-ArcTM technology especially for the deposition of ta-C coatings. The technology has meanwhile been tested in many applications. The process is based on pulsed vacuum arc discharges. Short laser pulses ignite the arc at well-defined locations on the cathode roll, which is made from graphite. This generates completely ionized plasma pulses of highly energetic carbon particles. The superposition of the linear displacement of the laser focus and the cathode rotation ensures the homogeneous carbon deposition over the entire length of the cathode as well as a uniform erosion of the cathode.
To ensure the Laser-ArcTM technology’s independence from any specific coating machine it was designed and implemented as a modular concept. The carbon plasma source is placed in a separate chamber. The module type LAM 500 was designed for a coating height of 500 mm to be suitable for PVD batch coaters as they are used in toll coating services. The Laser-ArcTM module chamber is attached to the PVD unit via a rectangular connector flange. All basic functions (i.e. vacuum generation, part movement, plasma cleaning, standard coating technologies) of the PVD coater remain intact and undisturbed. The concept enables new deposition possibilities for ta-C coatings.