Abstract:
The emission of microdroplets from the cathode surface in the vacuum arc ion plating deposition
techniqle is the major drawback to the technique's industrial use. The generation of these particles
from graphite cathodes is studied in this article and correlated to the local thermal load in the
cathode spot area. A pulse discharge was used for a precise control of this load. Increases in the arc
current level, arc duration time, and, more generally, the local temperature of the cathode were
found to increase the number and the average size of the emitted particles. Particles under these
conditions also show an increase in the width of their size distributions. Increasing the distance
between cathode and substrate was found to decrease the number density of particles observed on
the substrate according to the solid angle covered. The microdroplets show a graphite structure and
diameters between 0.2 and 2.0 p,m. Conditions needed to decrease the number of particles emitted
to the substrate are given.