ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
A prototype rf ion source for extracting a hydrogen-ion beam has been developed. The system consists of a rf source and a water-cooled quartz tube, which contains the plasma. The rf power is coupled through a four-turn coil located outside the tube. A perforated metal grid and an aperture located about 8 mm from the grid has an opening of 5 mm in diameter. The axially extracted beam is transported through a column of about 1 m maintained at a pressure of 10−4 Torr, while the pressure in the plasma region is about 10−2 Torr. The rf source is a class-C, variable-power oscillator of fixed frequency 7 MHz. Operating the system with about 300 W in the discharged plasma, a continuous proton beam of 55 μA has been observed at a distance of 10 cm from the extracter at a voltage of 2.5 kV. Under similar operating conditions an argon-ion beam of 14 μA has been extracted. Experiments are in progress to optimize the extraction of ions at 10 kV, increase the rf power, and provide a suitable focusing system to transport the beam at a distance of 1 m with maximum efficiency.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1141953