摘要 |
An electron beam column comprises a thermal field emission electron source to generate an electron beam, an electron beam blanker, a beam shaping module, and electron beam optics comprising a plurality of electron beam lenses. In one version, the optical parameters of the electron beam blanker, beam shaping module, and electron beam optics are set to achieve an acceptance semi-angle beta of from about ¼ to about 3 mrads, where the acceptance semi-angle beta is half the angle subtended by the electron beam at the writing plane. The beam-shaping module can also operate as a single lens using upper and lower projection lenses. A multifunction module for an electron beam column is also described.
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