Patent ID: 6271529
Filing Date: 2001-08-07
Classification: H01J,H05H

Abstract:
An ion implanter for implanting ions in a workpiece, comprisingapparatus for generating an ion beam and directing it toward a surface of a work piece, anda plasma generator for generating plasma to neutralize the ion beam and the work piece surface, the plasma generator comprisinga plasma generator chamber defined by walls,a relatively narrow outlet aperture for plasma produced in the chamber to leave the chamber to neutralize the beam and work piece surface,at least one cathode,at least one anode spaced from the cathode and from the walls of the chamber,magnets arranged within the plasma generator chamber, adjacent the chamber walls to generate a magnetic field to deflect primary electrons emitted from the cathode from directly reaching the anode, anda conductive shield, positioned within the chamber between the anode and the magnets, the shield having an electric potential selected to deflect electrons, the magnetic field and the conductive shield effective during operation to cause electrons from the cathode to trace extended paths to ionize gas within the chamber to generate plasma before reaching the anode.