| 摘要 |
Magnetic lenses and coils for magnetic lenses, charged-particle-beam (CPB) optical systems and pattern-transfer apparatus comprising such magnetic lenses, and manufacturing methods for such lenses, systems, and apparatus are disclosed. In the coils for magnetic lenses, the number of coil turns per unit length is adjusted so that the axial magnetic field at the ends of the coils more closely approximates an ideal magnetic field. In another example, a coil for a magnetic lens comprises two or more subcoils. The currents in the subcoils or the products of current and coil turns for respective subcoils are adjusted to approximate a selected magnetic field, such as to correct or at least reduce magnetic field "droop" at the ends of the coil. Magnetic lenses including such coils and a yoke are provided as well as CPB pattern-transfer apparatus using these magnetic lenses.
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