Patent ID: 8134130
Filing Date: 2012-03-13
Classification: H01J

Abstract:
1. An ion source, comprising: a first electrode comprising a repeller having a V-shaped groove defined by a pair of planar surfaces symmetrically disposed at an angle to each other, the V-shaped groove including a base defined by a line of intersection of the pair of planar surfaces; a second electrode comprising an electron emitter filament disposed adjacent the base of the V-shaped groove midway between the pair of planar surfaces and in the angle between the pair of planar surfaces, the electron emitter filament having a longitudinal axis that is substantially parallel to the base of the V-shaped groove; and a third electrode comprising an anode, the anode defining an enclosed volume having an aperture formed therein adjacent the electron emitter filament, wherein a center of the aperture lies in a plane that contains the base of the V-shaped groove and the longitudinal axis of the electron emitter filament; wherein a potential of the first electrode is less than a potential of the second electrode and the potential of the second electrode less than a potential of the third electrode.