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| FACTORS AFFECTING ION REACTION
IN THE PLASMA |
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| RF Power |
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Energy source for ionization to excite gas atoms |
| Why RF |
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Ion particles are generally excited with electric
fields, but pulsing is needed to compensate charge of ion to counter
react before its charge decays. |
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Excites ion more violently and radicals |
| Vacuum |
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Vacuum creates an atmosphere to increase boiling
point at low temperature |
| Reaction Gas |
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Inert gas if excited in a Plasma invironment creates
radical ion |
| Sheath |
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The region of strong electric field in front of
material surface in contact with a plasma Its thickness is the
Ion Sheath Length. |
| Debye Shield |
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If a plate or metal may it be negative or positive
charge is inserted into a plasma, it will change the local charge
distribution by attracting or repelling electrons. The net result
is an additional negative or positive charge density which cancles
the effect of the initial charge at distances large compared to
the debye length.
There is a corresponding effect of shielding by ions, which, for
various and subtle reasons |
| Van Allen Belt |
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The magnetic belt regions in which charged particles
are trapped by the magnetic mirror effect. |
| Mirror Effect |
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A charged particle travelling into an increasing
magnetic field will reverse direction and be reflected back, provided
its velocity perpendicular to to the field is sufficiently large
relative to its parallel velocity. This magnetic mirror effect
is a direct result of the adiabatic invariance of the magnetic
moment. The mirror effect occurs in some plasmas, since the toroidal
magnetic field is stronger on the inboard side than on the outboard
side; in this case it gives rise to so-called " neoclassic" bahavior. |