The present disclosure provides one embodiment of a method for extreme ultraviolet lithography (EUVL) process. The method includes loading a mask to a lithography system. The mask includes defect-repaired regions and defines an integrated circuit (IC) pattern thereon. The method also includes setting an illuminator of the lithography system in an illumination mode according to the IC pattern, configuring a pupil filter in the lithography system according to the illumination mode and performing a lithography exposure process to a target with the mask and the pupil filter by the lithography system in the illumination mode.

A method and system for adjusting exposure intensity to reduce unwanted lithographic effects is disclosed. In some exemplary embodiments, the method of photolithography includes receiving a mask and a workpiece. An orientation of an illumination pattern relative to the mask is determined, and an intensity profile of the illumination pattern is adjusted according to the orientation. The mask is exposed to radiation according to the illumination pattern and the intensity profile. Radiation resulting from the exposing of the mask is utilized to expose the workpiece. In some such embodiments, the intensity profile includes an intensity that varies across an illuminated region of the illumination pattern.

An imaging optical system for a projection exposure system has at least one anamorphically imaging optical element. This allows a complete illumination of an image field in a first direction with a large object-side numerical aperture in this direction, without the extent of the reticle to be imaged having to be enlarged and without a reduction in the throughput of the projection exposure system occurring.

The illumination optical system for illuminating an illumination target surface with light from a light source is provided with a polarization converting member which converts a polarization state of incident light to form a pupil intensity distribution in a predetermined polarization state on an illumination pupil of the illumination optical system; and a phase modulating member which is arranged in the optical path on the illumination target surface side with respect to the polarization converting member and which transmits light from the pupil intensity distribution so as to convert linearly polarized light thereof polarized in a first direction, into required elliptically polarized light and maintain a polarization state of linearly polarized light polarized in a second direction (X-direction or Y-direction) obliquely intersecting with the first direction, in order to reduce influence of retardation caused by a subsequent optical system between the polarization converting member and the illumination target surface.

An illumination optical system includes: a mirror part that converges light; a light source part that is disposed at a first focus of the mirror part and emits the light; a first aperture that is disposed at a second focus different from the first focus of the mirror part, absorbs a portion of the light converged at a plane of the second focus, and transmits a first light; a lens part spaced apart from the mirror part with the first aperture interposed between the mirror part and the lens part; a second aperture that is disposed between the first aperture and the lens part, absorbs a portion of the first light, and transmits a second light; and a cooling member that compensates for a temperature of the second aperture.