APPARATUS FOR MAGNETICALLY SCANNING AND/OR SWITCHING A CHARGED-PARTICLE BEAM

摘要

An apparatus is provided for deflecting a charged particle beam of a time-varying magnetic field emitted by a magnet with a laminated magnetic core and a non-conductive vacuum chamber placed in a gap of the laminated magnetic core. The charged particle beam travels in the vacuum through the time varying magnetic field to switch between beams of different ion species or to scan a single ion species with a controlled velocity across a target. The vacuum chamber includes multiple thin annular sheets of metal or of another conductive material placed within the vacuum chamber to dispose the charged particle beam that passes through holes in each annular sheet without striking the non-conductive vacuum chamber walls. Each annular sheet is electrically connected to each other in a manner that suppresses eddy currents that would otherwise be induced by the time-varying magnetic field. The apparatus can be extended to two dimensions at the cost of added complexity.