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Simplified beam line for low energy Ion implantation is considered. Compensation of the space charge of high perveance, low energy ion beam in beam lines for ion implantation and isotope separation has been investigated. Space charge compensation and overcompensation by ions will be considered. Different mechanisms of the compensating particle formation such as ionization by the beam, secondary emission of electrons and negative ions, electronegative gas admixture, and external plasma sources will be discussed. Advanced space charge compensation increases an intensity of low energy ion beam after analyzer magnet up to 3–4 times. Space charge compensation of positive ion beam by admixture of electronegative gases and damping of the beam instability will be discussed. Up to 6 mA of 11B+ ions with energy 3 keV, 11 mA with 5 keV, and 18 mA with 10 keV have been transported through an analyzer magnet of a high current implanter with space charge compensation by electronegative gases
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