| 摘要 |
Charged-particle-beam ("CPB"; e.g., electron-beam) apparatus are disclosed that exhibit reduce image blur due to space-charge effects. With such apparatus, a reticle pattern can be imaged on a substrate with greater accuracy and higher throughput. Such results can be achieved using a charged-particle source having comparatively low emittance. An illumination-optical system directs an illumination beam from a CPB source to a reticle defining a pattern to be transferred to a substrate. A projection-optical system projects, onto the substrate, imaging the beam that has passed through and has been patterned by the reticle. The illumination-optical system includes a beam-shaping aperture that causes the illumination beam to have an annular transverse profile. The reticle is illuminated with an image of a crossover of the illumination beam. The CPB source desirably emits the illumination beam from an annular region of a cathode. Thus, the illumination beam has a substantially uniform intensity distribution in the vicinity of a crossover formed by the CPB source, and this crossover is imaged in a plane that is optically conjugate with the reticle.
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