摘要 |
The present invention relates to an electron lens for use in an microcolumn, and more particularly to a multipole electron lens wherein the electron lens includes two or more electrode layers, each of the electrode layers has a slit aperture extending across a central optical axis along which an electron beam passes, and the two electrode layers are aligned on an electron optical axis such that the slit apertures are staggered with each other. Further, the present invention relates to a microcolumn using the multipole lens. The multipole lens according to the present invention can be manufactured and controlled in a simple fashion, reduces the defocusing of the microcolumn, and increases an active deflection area. |