Patent ID: 8698093
Filing Date: 2014-04-15
Classification: H01J

Abstract:
1. An electron beam apparatus comprising: an electron source for generating a primary electron beam; a magnetic immersion objective lens configured to focus the primary electron beam onto a surface of a target substrate; a pole piece of the magnetic immersion objective lens; an electrostatic deflector including a plurality of plates configured within the pole piece; an electrostatic lens field determined by the pole piece and the electrostatic deflector, wherein the electrostatic lens field is configured to be controllably adjusted by applying DC offset voltages to all of the plates of the electrostatic deflector; a top shunt configured within the pole piece above the electrostatic deflector such that the primary electron beam passes through an opening in the top shunt before passing through the electrostatic deflector, wherein a high voltage is applied to the pole piece, and wherein the top shunt is conductively connected to an electrical ground.