摘要 |
A microlithography projection apparatus comprises an illuminator, for supplying a beam of radiation for illuminating a pattern on a mask, and a projection system for forming an image of the illuminated portion of the mask on a resist-coated substrate. The image is projected off-axis with respect to the optical axis of the projection system and the aperture of the illuminator is minimized to that of the illuminated portion of the mask. The illuminator is provided with a compensator, such as a tiltable mirror or wedge-like transmissive optical element for compensating for telecentricity errors intrinsic to the projection system.
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