Der Hochstrombogen - eine neue Quelle der Hochratebeschichtung

A new type of arc evaporator will be described which was developed to improve the deposition rate for 5 times in comparison to an ordinary arc evaporation unit. This device, the so called high current pulsed arc (HCA) makes use of pulsed arc discharges with nearly sinusoidal current shapes which can be ignited repetitively by a high voltage pulse supplied to a trigger electrode, situated in the center of a circular cathode. The repetition rate can be changed between 0 and 300 Hz. The new arc evaporator can operate with an averaged arc current as high as 1000 A. The very controllable arc duration means that only a well defined circular area of erosion surrounding the point of ignition is effected by the arc evaporation. Beside the high rate, the HCA has some more adventages : - The deposition rate can easily be controlled and adjusted in the range from zero to maximum value. - The pulsed arc operates with peak rates about 20 times higher than an ordinary arc evaporation unit results in modulated film structure and/or chem. composition - The number of droplets will be strongly diminished. - Using two or more evaporation units, films with a well defined modulated composition and structure can be produced effectively and highly reproducible All the advantages of the vacuum arc deposition will be preserved. Results of deposition tests using different target materials, as Ti, AI, TiAl-alloy, Cu, steel are presented