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Refractory metal plasma generated by a vacuum arc was used to deposit thin films with different arc currents I. The deposition rate V dep was measured for electrode configurations including a planar Zr cathode and a planar W anode; cylindrical W or Mo electrode pairs and a cylindrical Nb cathode closed by a BN plate and a W or Nb shower-head cup anode or with one-hole Ta cup anode. V dep for a Mo electrode pair with I = 275 A at a distance L = 110 mm from the electrode axis reached 2.2 µm/min, 60 s after arc ignition. For the W electrode pair V dep was ∼1 µm/min at 80 s (I = 200 A and L = 110 mm), while for W film deposition with shower-head anode V dep was ∼0.6 µm/min (I = 200 A and L = 60 mm). For Nb films deposited with the closed electrode configuration, V dep was 0.3 µm/min at 30 s after arc ignition (I = 275 A and L = 80 mm from the anode front).Index Terms-Metallic plasma, refractory electrode, thin film, vacuum arc.

The energy dissipated in the cathode in a vacuum arc black body assembly (VABBA) is investigated. A closed volume is formed by a water-cooled cylindrical Cu cathode and a cup-shaped W or Ta anode. Cu cathode material is emitted into the closed volume and the anode is heated by the arc. The VABBA confined and evaporated macroparticles while the plasma is extracted through small anode apertures. Arc currents are I = 175-250 A and the arc time is 150 s. The effective cathode voltage U cef is determined calorimetrically, using a thermocouple probe. It is observed that U cef increases with time from ∼6.5 V for cold anodes (i.e., during conventional cathodic arcing) to a steady-state value of ∼11.2-12.0 V when the anode is sufficiently hot and the arc operated in the VABBA mode.Index Terms-Calorimetric method, cathodic arc, effective cathode voltage, thermocouple probe, vacuum arc.