EUV condenser with non-imaging optics

摘要

An illumination system and condenser for use in photolithography in the extreme ultraviolet wavelength region having a first non-imaging optic element (14) collecting electromagnetic radiation from a source (12) and creating a desired irradiance distribution and a second non-imaging optic element (18) receiving the electromagnetic radiation from the first non-imaging optic element (14) and redirecting and imaging the electromagnetic radiation. The electromagnetic radiation emanating from the second non-imaging optic element (18) is suitable for being received by other conventional optical surfaces to provide a desired irradiance distribution with a desired angular distribution and desired shape. Facets (34) are used to provide the desired illumination over the desired illumination field. Reflective facets (34) may be placed on the second non-imaging optic, which can reduce the number of mirrors and increase efficiency. The condenser and illumination system are used in combination with a projection optic (36) to project the image of a reticle or mask (30) onto a photosensitive substrate (50), such as a semiconductor wafer used in the manufacture of electronic or semiconductor devices. The condenser of the present invention provides an efficient condenser in a compact package and provides desirable illumination properties for imaging relatively small feature sizes less than 0.13 microns.