Improving Efficiency of Ions Production in Ion Source with Saddle Antenna
نویسندگان
چکیده
Extraction of positive and negative ions from a saddle antenna radio-frequency surface plasma source (SA RF SPS) is considered. Several versions of new plasma generators with different antennas and magnetic field configurations were tested in the small Test Stand. The efficiency of positive ion generation in plasma has been improved up to 80 times from 2.5 mA/cm kW to ~0.2 A/cm per 1 kW. For cesiation was used a heating of the cesium chromate cartridges. A small oven for cesium compounds and alloys decomposition by heating was developed and tested. After cesiation a current of negative ions to the collector was increased from ~1 mA to 10 mA with RF power ~ 1.5 kW in the plasma and longitudinal magnetic field Bl~250 Gauss. A specific efficiency of H production was increased up to ~ 20 mA/ cm kW from previous ~2.5 mA/ cm kW.
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