An imaging optical system has a plurality of mirrors which image an object field in an object plane in an image field in an image plane. The imaging optical system has a pupil obscuration. The last mirror in the beam path of the imaging light between the object field and the image field has a through-opening for the passage of the imaging light. A penultimate mirror of the imaging optical system in the beam path of the imaging light between the object field and the image field has no through-opening for the passage of the imaging light. The result is an imaging optical system that provides a combination of small imaging errors, manageable production and a good throughput for the imaging light.

There is provided a reflective image-forming optical system which is applicable to an exposure apparatus using, for example, EUV light and which is capable of increasing numerical aperture while enabling optical path separation of light fluxes. In a reflective imaging optical system (6) forming an image of a first plane (4) onto a second plane (7), the numerical aperture on a side of the second plane with respect to a first direction (X direction) on the second plane is greater than 1.1 times a numerical aperture on the side of the second plane with respect to a second direction (Y direction) crossing the first direction on the second plane. The reflecting imaging optical system has an aperture stop (AS) defining the numerical aperture on the side of the second plane, and the aperture stop has an elliptic-shaped opening of which size in a major axis direction (X direction) is greater than 1.1 times that in a minor axis direction (Y direction).

A super-resolution system for nano-patterning is disclosed, comprising an exposure head that enables a super-resolution patterning exposures. The super-resolution exposures are carried out using electromagnetic radiation and plasmonic structures, and in some embodiments, plasmonic structures having specially designed super-resolution apertures, of which the bow-tie and C-aperture are examples. These apertures create small but bright images in the near-field transmission pattern. A writing head comprising one or more of these apertures is held in close proximity to a medium for patterning. In some embodiments, a data processing system is provided to re-interpret the data to be patterned into a set of modulation signals used to drive the multiple individual channels and multiple exposures.

An imaging optical unit for projection lithography has a plurality of mirrors for guiding imaging light from an object field in an object plane into an image field in an image plane along an imaging light beam path. At least two of the mirrors are embodied as GI mirrors. Exactly one stop serves to predefine at least one section of an outer marginal contour of a pupil of the imaging optical unit. The stop is arranged spatially in front of a penultimate mirror in the imaging light beam path. This results in an imaging optical unit that is well defined with regard to its pupil and is optimized for projection lithography.

A super-resolution system for nano-patterning is disclosed, comprising an exposure head that enables a super-resolution patterning exposures. The super-resolution exposures are carried out using electromagnetic radiation and plasmonic structures, and in some embodiments, plasmonic structures having specially designed super-resolution apertures, of which the bow-tie and C-aperture are examples. These apertures create small but bright images in the near-field transmission pattern. A writing head comprising one or more of these apertures is held in close proximity to a medium for patterning. In some embodiments, a data processing system is provided to re-interpret the data to be patterned into a set of modulation signals used to drive the multiple individual channels and multiple exposures, and a detection means is provided to verify the data as written.

There is provided a reflective image-forming optical system which is applicable to an exposure apparatus using, for example, EUV light and which is capable of increasing numerical aperture while enabling optical path separation of light fluxes. In a reflective imaging optical system (6) forming an image of a first plane (4) onto a second plane (7), the numerical aperture on a side of the second plane with respect to a first direction (X direction) on the second plane is greater than 1.1 times a numerical aperture on the side of the second plane with respect to a second direction (Y direction) crossing the first direction on the second plane. The reflecting imaging optical system has an aperture stop (AS) defining the numerical aperture on the side of the second plane, and the aperture stop has an elliptic-shaped opening of which size in a major axis direction (X direction) is greater than 1.1 times that in a minor axis direction (Y direction).

A lithographic apparatus (10) and method for preventing exposure of a peripheral portion (P) of a substrate (S). An edge mask (M) has a radial concave edge (E) that extends over less than half a circle arch. The edge mask (M) is connected to a mask carrier (4) that circumnavigates the projection system (2) to adjust a tangential coordinate () and a radial coordinate (R) of the edge mask (M) with respect to the optical axis (A) of the projection system (2) for inserting the edge mask (M) at a variable distance into the beam of radiation (B). The tangential and radial positions (,R) of the edge mask (M) are coordinated with a changing position (X,Y) of the substrate (S) to prevent exposure of the peripheral portion (P) of the substrate (S) during exposure of the target region (T).

An super-resolution system for nano-patterning is disclosed, comprising an exposure head that enables a super-resolution patterning exposures. The super-resolution exposures are carried out using electromagnetic radiation directed onto a medium using plasmonic structures, and in particular using plasmonic structures using specially designed super-resolution apertures, of which the bow-tie and C-aperture are examples. These specially designed apertures create small but bright images in the near-field transmission pattern. A printing head comprising an array of these apertures is held in close proximity to a medium for patterning. In some embodiments, a data processing system is provided to re-interpret the data to be patterned into a set of modulation signals used to drive the multiple individual channels and multiple exposures.

An imaging optical unit for EUV projection lithography serves to image an object field into an image field. Mirrors guide imaging light from the object field to the image field. An aperture stop is tilted by at least 1 in relation to a normal plane which is perpendicular to an optical axis. The aperture stop has a circular stop contour. In mutually perpendicular planes, a deviation of a numerical aperture NA.sub.x measured in one plane from a numerical aperture NA.sub.y measured in the other plane is less than 0.003, averaged over the field points of the image field. What emerges is an imaging optical unit, in which homogenization of an image-side numerical aperture is ensured so that an unchanging high structure resolution in the image plane is made possible, independently of an orientation of a plane of incidence of the imaging light in the image field.

A method and system for fracturing or mask data preparation or optical proximity correction or proximity effect correction or mask process correction is disclosed in which a set of shaped beam shots is determined that is capable of forming a pattern on a surface, where the set of shots provides different dosages to different parts of the pattern, and where the dose margin from the set of shots is calculated. A method for forming patterns on a surface is also disclosed.