摘要 |
One embodiment relates to an electron source apparatus for an electron beam lithography tool or an electron beam inspection tool. A cathode is configured to emit electrons, and an anode is configured to accelerate the electrons so as to create an electron beam. There are no beam apertures in the electron source apparatus that are positioned at non-focal planes. An electron lens may be configured to focus the electron beam to form a cathode image at a focal plane, and a beam aperture may positioned at the focal plane. Other embodiments, aspects and features are also disclosed. |