Extreme Ultraviolet Lithography Projection Optics System and Associated Methods

摘要

The present disclosure provides an extreme ultraviolet lithography system. The extreme ultraviolet lithography system includes a projection optics system to image a pattern of a mask on a wafer. The projection optics system includes between two to five mirrors. The two to five mirrors are designed and configured to have a numerical aperture less than about 0.50, an image field size at the wafer hat is greater than or equal to about 20 mm, and a pupil plane that includes central obscuration. In an example, the central obscuration has a radius that is less than or equal to 50% of a radius of the pupil plane. In an example, the central obscuration has an area that is less than or equal to 25% of an area of the pupil plane.