Negative ion source with low temperature transverse divergence optical system

Patent · Tue Jul 22 04:00:00 EDT 1986

OSTI ID:5453840

Whealton, J H; Stirling, W L

This patent describes an ion source for generating a beam of negative ions from a selected molecular species wherein the selected molecular species is introduced in a gaseous state into a chamber formed by an electrically conductive housing and including a converter plate having an ion converter surface disposed within the chamber, an ion extraction electrode forming a part of the housing disposed in front of the converter plate and having an exit slit therein through which the beam of negative ions produced in the chamber exit the chamber, an acceleration electrode disposed parallel to and spaced from the extraction electrode for accelerating the negative ions passing through the exit slit of the extraction electrode through the corresponding opening in the acceleration electrode. The converter plate is operated at a first potential relative to the housing so that positive ions of the species generated in a discharge plasma column extending over and spaced from the ion converter surface are accelerated into the converter surface to convert the positive ions to negative ions of the species by means of surface ionization and subsequently ejected from the converter surface back through the plasma column toward the exit slit in the extraction electrode and wherein the ion source is immersed in a magnetic field extending parallel to the converter surface.

• Assignee: Dept. of Energy, Washington, DC
• Patent Number(s): US 4602161
• OSTI ID: 5453840
• Country of Publication: United States
• Language: English

Related Subjects

640301* -- Atomic
Molecular & Chemical Physics-- Beams & their Reactions
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCELERATION
ANIONS
BEAM EXTRACTION
BEAM OPTICS
BEAMS
CHARGED PARTICLES
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRODES
FLUIDS
GASES
INCIDENCE ANGLE
ION BEAMS
ION SOURCES
IONIZATION
IONS
MAGNETIC FIELDS
MOLECULES
OPTICAL SYSTEMS
PHYSICAL PROPERTIES
PLASMA
POSITIONING
SPACE DEPENDENCE
SURFACE AREA
SURFACE IONIZATION
SURFACE PROPERTIES
TEMPERATURE DEPENDENCE