Particle beam shielding

摘要

An apparatus is described for allowing an ion beam and an electron beam to travel toward a predetermined region of a substrate surface during the sputter etching and imaging of insulating and other targets while preventing deflection of the electron beam by sources of stray electrostatic fields on the substrate surface. A metal shield is provided having a funnel-shaped portion leading to an orifice. The incident finely focused ion beam, together with the electron beam, which is used to neutralize the charge created by the incident ion beam, pass to the target through the orifice. The shield also physically supports a gas injection needle that injects a gas through the orifice toward the predetermined region.