Duopigatron ion source studies

Technical Report · Sat Jul 01 04:00:00 EDT 1978

DOI:https://doi.org/10.2172/6621789· OSTI ID:6621789

Bacon, F M; Bickes, Jr, R W; O'Hagan, J B

Ion source performance characteristics consisting of total ion current, ion energy distribution, mass distribution, and ion current density distribution were measured for several models of a duopigatron. Variations on the duopigatron design involved plasma expansion cup material and dimensions, secondary cathode material, and interelectrode spacings. Of the designs tested, the one with a copper and molybdenum secondary cathode and a mild steel plasma expansion cup proved to give the best results. The ion current density distribution was peaked at the center of the plasma expansion cup and fell off to 80 percent of the peak value at the cup wall for a cup 15.2 mm deep. A total ion current of 180 mA consisting of 60 to 70 percent atomic ions was produced with an arc current of 20 A and source pressure of 9.3 Pa. More shallow cups produced a larger beam current and a more sharply peaked ion current density distribution. Typical ion energy distributions were bell-shaped curves with a peak 10 to 20 V below anode potential and with ion energies extending 30 to 40 V on either side of the peak.

• Research Organization: Sandia Labs., Albuquerque, NM (USA)
• DOE Contract Number: EY-76-C-04-0789
• OSTI ID: 6621789
• Report Number(s): SAND-77-1789
• Country of Publication: United States
• Language: English

Related Subjects

640301* -- Atomic
Molecular & Chemical Physics-- Beams & their Reactions
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALLOYS
BEAM CURRENTS
BEAM PROFILES
CATHODES
COPPER
CURRENTS
DESIGN
DIMENSIONS
DUOPLASMATRONS
ELECTRIC DISCHARGES
ELECTRODES
ELECTRON TUBES
ELEMENTS
ENERGY SPECTRA
ION SOURCES
IRON ALLOYS
IRON BASE ALLOYS
METALS
MOLYBDENUM
PENNING DISCHARGES
PENNING ION SOURCES
PLASMATRONS
REFRACTORY METALS
SPECTRA
STEELS
TRANSITION ELEMENTS