Patent ID: 6576908
Filing Date: 2003-06-10
Classification: H01J

Abstract:
A charged particle beam column comprising:a first vacuum chamber (1); a particle source (3) for providing a beam of charged particles (4) propagating along an optical axis (9); a multi aperture unit (5) comprising at least two beam defining apertures (6) for shaping the beam of charged particles, the particle source and the beam defining apertures being located within the first vacuum chamber; a separation unit (7) for isolating a second vacuum chamber (2) from the first vacuum chamber whereby the separation unit comprises a path aperture (8) for the charged particle beam; a first deflecting unit (11) for directing the beam of charged particles through one of the beam defining apertures (6); and a second deflecting unit (12) for directing the beam of charged particles through the path aperture (8).