Arc cathode spots: Their mechanism and motion

Continuous cathodic Arc sources

“…Experimentally, the arc-spot motion is influenced by several controllable conditions: applied magnetic field, [12] background gas pressure, cathode temperature, [13] and to a lesser extent, the cathode material: …”

Unstable arc operation and cathode spot motion in a magnetically filtered vacuum-arc deposition system

“…25,33 With the imposition of a magnetic field, the spots tend ͑a͒ to move in the ''retrograde'' ͑؊J؋B͒ direction, [23][24][25][26][27][28][29][30][31] and ͑b͒ if the magnetic field lines intersect the cathode surface at an angle, then the spots will have a velocity component towards the opening of the acute angle formed by the field line-cathode surface intersection. Without an imposed magnetic field, the cathode spot motion is random.…”

Observation of dust stream formation produced by low current, high voltage cathode spots

“…The plasma column associated with the cathode spot can also charge up nearby particles, and subsequently accelerate them as well. The high plasma pressure formed at the cathode spot root 16,18 also locally accelerates dust particles. This process is similar to the plasma drag accelerator used for micrometeoroid simulation.…”

“…Cathodes spots can be initiated by the very high electric fields present at the surface. [14][15][16][17][18] In general, cathode spots are typically low voltage, high current, vacuum arc phenomena. Though rare, the low current, high voltage spot has also been documented in the literature.…”