| Arc Vapor Deposition
is firstly introduced by D. M. Mattox
in 1963. According to his definition,
Arc Vapor Deposition is distinguished
from other deposition method by the
significant feather of ˇ°the high percentage
of ionization of the material vaporized
from the electrodes, as well as ionization
of the gases that may be present.
The ions of the vaporized material
(ˇ°film-ionsˇ± or ˇ°self-ionsˇ±) may be
accelerated to high kinetic energies.ˇ±
Since the above mentioned definition
did not define how the target is vaporized
or how the bombarding ions are generated,
Arc Vapor Deposition can have many
varieties.
Multi
Arc Ion Deposition
The arc evaporation process begins
with the striking of a high current,
low voltage arc on the surface of
a cathode (known as the target) that
gives rise to a small (usually a few
micrometers wide), highly energetic
emitting area known as a cathode spot.
The localized temperature at the cathode
spot is extremely high (around 15000
ˇăC), which results in a high velocity
(10 km/s) jet of vaporized cathode
material, leaving a crater behind
on the cathode surface. The cathode
spot is only active for a short period
of time, then it self-extinguishes
and re-ignites in a new area close
to the previous crater. This behavior
causes the apparent motion of the
arc.
As the arc is basically a current
carrying conductor it can be influenced
by the application of an electromagnetic
field, which in practice is used to
rapidly move the arc over the entire
surface of the target, so that the
total surface is erod ed over
time.
The arc has an extremely high power
density resulting in a high level
of ionization (30-100%), multiply
charged ions, neutral particles, clusters
and macro-particles (droplets). If
a reactive gas is introduced during
the evaporation process, dissociation,
ionization and excitation can occur
during interaction with the ion flux
and a compound film will be deposited.
Advantages of Multi Arc Ion Deposition
include high speed of evaporation
speed, high density, hardness and
duribility of the deposited film,
etc.
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