Non-ambipolar radio-frequency plasma electron source and systems and methods for generating electron beams
- Madison, WI
An electron generating device extracts electrons, through an electron sheath, from plasma produced using RF fields. The electron sheath is located near a grounded ring at one end of a negatively biased conducting surface, which is normally a cylinder. Extracted electrons pass through the grounded ring in the presence of a steady state axial magnetic field. Sufficiently large magnetic fields and/or RF power into the plasma allow for helicon plasma generation. The ion loss area is sufficiently large compared to the electron loss area to allow for total non-ambipolar extraction of all electrons leaving the plasma. Voids in the negatively-biased conducting surface allow the time-varying magnetic fields provided by the antenna to inductively couple to the plasma within the conducting surface. The conducting surface acts as a Faraday shield, which reduces any time-varying electric fields from entering the conductive surface, i.e. blocks capacitive coupling between the antenna and the plasma.
- Research Organization:
- Univ. of Wisconsin, Madison, WI (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- FG02-97ER54437
- Assignee:
- Wisconsin Alumni Research Foundation (Madison, WI)
- Patent Number(s):
- 7,498,592
- Application Number:
- 11/427,273
- OSTI ID:
- 973142
- Country of Publication:
- United States
- Language:
- English
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