Patent ID: 7569833
Filing Date: 2009-08-04
Classification: B82Y,H01J

Abstract:
1. An apparatus for generating a plurality of charged particle beamlets, comprising: a charged particle source for generating a diverging charged particle beam, a lens array comprising a plurality of lenses, said lens array further comprising an aperture plate, wherein the aperture plate has an electrically conducting surface and means for defining the electrostatic potential of said surface, and means for defining an equipotentional surface at a distance from said aperture plate at a different potential than said aperture itself, wherein said means comprises a plate placed at a distance from said aperture plate, wherein said plate having a hole large enough to let the beam pass, and means for defining the electrostatic potential of said plate at a different potential than said aperture plate, wherein the apparatus comprises a converging means for refracting said diverging charged particle beam, and wherein the converging means is adapted for refracting a diverging charged particle beam into a substantially parallel charged particle beam for generating a plurality of substantially parallel charged particle beamlets, wherein said converging means comprises a collimator lens and further comprises an array of converging elements, wherein each element comprises a deflector aligned with a beamlet.