Microwave plasma
Encyclopedia
Microwave plasma is a type of plasma
, that has high frequency electromagnetic radiation
in the GHz
range. It is capable of exciting electrode
less gas discharges.
, they are especially well suited to generate large-area plasmas of high plasma density. If they are both in surface-wave
and resonator mode
, they can exhibit a high degree of spatial localisation. This allows to spatially separate the location of plasma generations from the location of surface processing. Such a separation (together with an appropriate gas-flow scheme) may help reduce the negative effect, that particles released from a processed substrate may have on the plasma chemistry of the gas phase.
Plasma (physics)
In physics and chemistry, plasma is a state of matter similar to gas in which a certain portion of the particles are ionized. Heating a gas may ionize its molecules or atoms , thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions...
, that has high frequency electromagnetic radiation
Electromagnetic radiation
Electromagnetic radiation is a form of energy that exhibits wave-like behavior as it travels through space...
in the GHz
GHZ
GHZ or GHz may refer to:# Gigahertz .# Greenberger-Horne-Zeilinger state — a quantum entanglement of three particles.# Galactic Habitable Zone — the region of a galaxy that is favorable to the formation of life....
range. It is capable of exciting electrode
Electrode
An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit...
less gas discharges.
Properties of microwave-excited plasma
If applied in surface-wave-sustained modeSurface-wave-sustained mode
Plasmas that are excited by propagation of electromagnetic surface waves are called surface-wave-sustained. Surface wave plasma sources can be divided into two groups depending upon whether the plasma generates part of its own waveguide by ionisation or not. The former is called a self-guided plasma...
, they are especially well suited to generate large-area plasmas of high plasma density. If they are both in surface-wave
Surface-wave-sustained mode
Plasmas that are excited by propagation of electromagnetic surface waves are called surface-wave-sustained. Surface wave plasma sources can be divided into two groups depending upon whether the plasma generates part of its own waveguide by ionisation or not. The former is called a self-guided plasma...
and resonator mode
Resonator mode
In the resonator mode, the plasma density does not exceed thecritical density.A standing electromagnetic wave, which is confined by aresonator cavity, penetrates the plasma and sustains it in the regions of highest field...
, they can exhibit a high degree of spatial localisation. This allows to spatially separate the location of plasma generations from the location of surface processing. Such a separation (together with an appropriate gas-flow scheme) may help reduce the negative effect, that particles released from a processed substrate may have on the plasma chemistry of the gas phase.