Negative ion source

Patent · Sun Jan 01 00:00:00 EST 1984

OSTI ID:865274

Leung, Ka-Ngo ^[1]; Ehlers, Kenneth W ^[2]

---

1. Hercules, CA
2. Alamo, CA

An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• DOE Contract Number: AC03-76SF00098
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4486665
• OSTI ID: 865274
• Country of Publication: United States
• Language: English

Related Subjects

negative
source
ionization
vessel
divided
ionizing
zone
extraction
magnetic
filter
prevents
high-energy
electrons
crossing
positive
voltage
impressed
plasma
grid
located
adjacent
positively
biases
prevent
migrating
low-energy
ordinarily
dragged
prevented
extracted
additional
suppressed
output
flux
exb
drift
provided
permanent
magnets
extractor
electrical
field
magnetic filter
electrical field
energy electrons
permanent magnet
permanent magnets
located adjacent
energy electron
extraction zone
additional electrons
extraction grid
filter prevents
positive voltage
ionizing zone
high-energy electron
high-energy electrons
/250/376/