Patent ID: 6093456
Filing Date: 2000-07-25
Classification: H01J

Abstract:
An ion implanter comprising an ion beam generator to generate a beam of ions for implantation in a substrate,a substrate holder for holding the substrate to be implanted whereby during implantation by the implanter the substrate on said holder at least partially and at least intermittently intercepts said beam,a beam stop including an ion absorber located behind said holder so as to absorb substantially all ions of said beam which are not intercepted by one of said holder and the substrate on said holder,said ion absorber having an ion absorbing surface which has a total area transverse to the beam which is greater than a cross-sectional area of the beam at the beam stop, and an adjustable support for the ion absorber for changing a position of said absorber relative to the beam to present different parts of said ion absorbing surface to the beam, such that each of said different parts can accommodate the cross-sectional area of the ion beam at the beam stop.