Method and apparatus for uniform charged particle irradiation of a surface

摘要

A method and apparatus which uses combined quadrupole (Qx and Qy) and multipole magnet sets (Mx and My) to focus a charged particle beam from a point source is described. Primarily the multipole magnet sets are octupole magnets. The apparatus is particularly useful for providing a uniform intensity for ion implantation, in cancer therapy and in other fields where uniform charged particle irradiation of a surface is important.