A reflective optical element (17), in particular for reflecting EUV radiation (16), includes: a substrate (25), and a reflective coating (26) applied to the substrate (25). In one disclosed aspect, the substrate (25) is doped within its volume (V) with at least one precious metal (27). In a further disclosed aspect, the reflective coating (26) and/or a structured layer (28) that is formed between the substrate (25) and the reflective coating (26) is doped with at least one precious metal (27). Also disclosed are an optical arrangement, preferably a projection exposure apparatus for microlithography, in particular for EUV lithography, which includes at least one such reflective optical element (17), and a method of producing such a reflective optical element (17).

A method of manufacturing a semiconductor device includes forming a photoresist layer over a substrate, selectively exposing the photoresist layer to an EUV radiation, and developing the selectively exposed photoresist layer. The photoresist layer has a composition including a solvent and a photo-active compound dissolved in the solvent and composed of a molecular cluster compound incorporating hexameric tin and two chloro ligands.

Disclosed is a method of measuring focus performance of a lithographic apparatus, and corresponding patterning device and lithographic apparatus. The method comprises using the lithographic apparatus to print one or more first printed structures and second printed structures. The first printed structures are printed by illumination having a first non-telecentricity and the second printed structures being printed by illumination having a second non-telecentricity, different to said first non-telecentricity. A focus dependent parameter related to a focus-dependent positional shift between the first printed structures and the second printed structures on said substrate is measured and a measurement of focus performance based at least in part on the focus dependent parameter is derived therefrom.

A mirror, such as for a microlithographic projection exposure apparatus, comprises an optical effective surface. The mirror comprises a mirror substrate and a plurality of cavities in the mirror substrate. Fluid can be applied to each cavity. A deformation is transferable to the optical effective surface by varying the fluid pressure in the cavities. Related optical systems methods are provided.

The disclosure provides a method for determining at least one property of an EUV source in a projection exposure apparatus for semiconductor lithography, wherein the property is determined on the basis of the electromagnetic radiation emanating from the EUV source, and wherein a thermal load for a component of the projection exposure apparatus is determined and the property is deduced on the basis of the thermal load determined.

A projection exposure method and apparatus are disclosed for exposing a radiation-sensitive substrate with at least one image of a pattern of a mask under the control of an operating control system of a projection exposure apparatus, part of the pattern lying in an illumination region is imaged onto the image field on the substrate with the aid of a projection lens, wherein all rays of the projection radiation contributing to the image generation in the image field form a projection beam path.

An optical system includes an illumination optical unit configured to guide illumination radiation along a path to an object plane. The illumination optical unit includes comprising a first facet mirror; a second facet mirror disposed downstream of the first facet mirror along the path; and a condenser mirror. The optical system also includes a projection optical unit configured to image a first article in the object plane onto a second article in an image plane. The image plane is a first distance from the object plane. The condenser mirror a second distance from the object plane. The second distance is greater than the first distance

An exposure apparatus according to the present invention includes an illumination optical system including a first optical modulation unit having a plurality of optical modulation elements, a second optical modulation unit having a plurality of optical modulation elements, and an imaging optical system forming optical images on a predetermined plane by using lights from the first optical modulation unit and the second optical modulation unit, and a projection optical system projecting the optical image formed on the predetermined plane onto a substrate.

An optical system, for example in a microlithographic projection exposure apparatus, comprises a mirror and a temperature-regulating device. The mirror has an optical effective surface and a mirror substrate. A plurality of temperature-regulating zones are arranged in the mirror substrate. The temperature-regulating device is used to adjust the temperatures present in each of the temperature-regulating zones independently of one another. The temperature-regulating zones are arranged in at least two planes at different distances from the optical effective surface. The temperature-regulating zones in the at least two planes are configured as cooling channels through which, independently of one another, a cooling fluid at a variably adjustable cooling fluid temperature is able to flow. A method for operating such an optical system is provided.

A facet mirror for an illumination optical unit of a projection exposure apparatus has a large number of displaceable individual facets with a facet main body and a reflection surface arranged on it. At least some of the individual facets have a displacement range such that they come into contact with a stop surface in one or more displacement positions.