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Title: Three chamber negative ion source

Abstract

A negative ion vessel is divided into an excitation chamber, a negative ionization chamber and an extraction chamber by two magnetic filters. Input means introduces neutral molecules into a first chamber where a first electron discharge means vibrationally excites the molecules which migrate to a second chamber. In the second chamber a second electron discharge means ionizes the molecules, producing negative ions which are extracted into or by a third chamber. A first magnetic filter prevents high energy electrons from entering the negative ionization chamber from the excitation chamber. A second magnetic filter prevents high energy electrons from entering the extraction chamber from the negative ionizing chamber. An extraction grid at the end of the negative ion vessel attracts negative ions into the third chamber and accelerates them. Another grid, located adjacent to the extraction grid, carries a small positive voltage in order to inhibit positive ions from migrating into the extraction chamber and contour the plasma potential. Additional electrons can be suppressed from the output flux using ExB forces provided by magnetic field means and the extractor grid electric potential.

Inventors:
 [1];  [2];  [3]
  1. Hercules, CA
  2. Alamo, CA
  3. Livermore, CA
Issue Date:
Research Org.:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
OSTI Identifier:
865705
Patent Number(s):
4559477
Assignee:
United States of America as represented by United States (Washington, DC)
Patent Classifications (CPCs):
H - ELECTRICITY H01 - BASIC ELECTRIC ELEMENTS H01J - ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
chamber; negative; source; vessel; divided; excitation; ionization; extraction; magnetic; filters; input; means; introduces; neutral; molecules; electron; discharge; vibrationally; excites; migrate; ionizes; producing; extracted; third; filter; prevents; energy; electrons; entering; ionizing; grid; attracts; accelerates; located; adjacent; carries; positive; voltage; inhibit; migrating; contour; plasma; potential; additional; suppressed; output; flux; exb; forces; provided; field; extractor; electric; electron discharge; magnetic filter; energy electrons; magnetic field; electric potential; ionization chamber; located adjacent; third chamber; energy electron; additional electrons; extraction grid; filter prevents; extraction chamber; input means; positive voltage; charge means; field means; vibrationally excite; producing negative; /315/250/313/

Citation Formats

Leung, Ka-Ngo, Ehlers, Kenneth W, and Hiskes, John R. Three chamber negative ion source. United States: N. p., 1985. Web.
Leung, Ka-Ngo, Ehlers, Kenneth W, & Hiskes, John R. Three chamber negative ion source. United States.
Leung, Ka-Ngo, Ehlers, Kenneth W, and Hiskes, John R. Tue . "Three chamber negative ion source". United States. https://www.osti.gov/servlets/purl/865705.
@article{osti_865705,
title = {Three chamber negative ion source},
author = {Leung, Ka-Ngo and Ehlers, Kenneth W and Hiskes, John R},
abstractNote = {A negative ion vessel is divided into an excitation chamber, a negative ionization chamber and an extraction chamber by two magnetic filters. Input means introduces neutral molecules into a first chamber where a first electron discharge means vibrationally excites the molecules which migrate to a second chamber. In the second chamber a second electron discharge means ionizes the molecules, producing negative ions which are extracted into or by a third chamber. A first magnetic filter prevents high energy electrons from entering the negative ionization chamber from the excitation chamber. A second magnetic filter prevents high energy electrons from entering the extraction chamber from the negative ionizing chamber. An extraction grid at the end of the negative ion vessel attracts negative ions into the third chamber and accelerates them. Another grid, located adjacent to the extraction grid, carries a small positive voltage in order to inhibit positive ions from migrating into the extraction chamber and contour the plasma potential. Additional electrons can be suppressed from the output flux using ExB forces provided by magnetic field means and the extractor grid electric potential.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 1985},
month = {Tue Jan 01 00:00:00 EST 1985}
}