In an embodiment, an apparatus includes an energy source, a support platform for holding a wafer, an optical path extending from the energy source to the support platform, and a photomask aligned such that a patterned major surface of the photomask is parallel to the force of gravity, where the optical path passes through the photomask, where the patterned major surface of the photomask is perpendicular to a topmost surface of the support platform.

Described is a telecentric illuminator that can be used, for example, in a mask aligner system for semiconductor wafer processing or as part of a solar simulator system for characterization of solar cells. The telecentric illuminator includes a tapered optic, a lens group having a plurality of lenses and an aperture stop, and a hybrid Fresnel lens. The Fresnel lens is disposed at a position along the optical axis of the telecentric illuminator to generate a telecentric image of the aperture stop at an illumination plane. The Fresnel lens may have a curved central portion and the aperture stop may be apodized to achieve desired illumination characteristics and improve the resolution of a mask aligner system.

An EUV collector has a reflection surface with a basic mirror shape of a spherical section. A diffraction grating for EUV used light is applied to the reflection surface. The diffraction grating is designed so that the EUV used light, which emanates from a sphere center of the spherical section, is diffracted by the diffraction grating toward a collection region. The collection region is spatially spaced apart from the sphere center. This creates an EUV collector in which an effective separation between EUV used light, which is to be collected with the aid of the collector, and extraneous light having a wavelength that differs from a used light wavelength is made possible.

A set of tracking devices can be placed within a geographic area as part of a scavenger hunt. A user with a mobile device can traverse the area, and when the user moves within a threshold proximity or communicative range of a tracking device, the mobile device can receive a communication from the tracking device identifying the tracking device. In response to determining that the tracking device is part of the set of tracking devices and thus part of the scavenger hunt, the mobile device can modify a tracking device interface displaying a representation of the tracking device to indicate that the tracking device has been found. In response to each tracking device being found, the mobile device can modify the tracking device interface to indicate that the scavenger hunt has been completed.

An illumination optical unit for EUV projection lithography includes a field facet mirror and a pupil facet mirror. A correction control device, which is used for the controlled displacement of at least some field facets that are usable as correction field facets, which are signal connected to displacement actuators, is embodied so that a correction displacement path for the correction field facets is so large that a respective correction illumination channel is cut off at the margin by the correction pupil facet so that the illumination light partial beam is not transferred in the entirety thereof from the correction pupil facet into the object field.

A radiation source contains a collector module comprising an optical collector, positioned in a vacuum chamber with an emitting plasma, further comprising a means for debris mitigation which include at least two casings arranged to output debris-free homocentric beams of the short-wavelength radiation, coming to the optical collector preferably consisting of several identical mirrors. Outside each casing there are permanent magnets that create a magnetic field inside the casings to mitigate charged fraction of debris particles and provide the debris-free homocentric beams of short-wavelength radiation. Other debris mitigating techniques are additionally used. Preferably the plasma is laser-produced plasma of a liquid metal target supplied by a rotating target assembly to a focus area of a laser beam. The technical result of the invention is the creation of high-powerful high-brightness debris-free sources of short-wavelength radiation with large, preferably more than 0.25 sr, collection solid angle.

A reflective optical element (1) for reflecting light having at least one wavelength in an EUV wavelength range has an optically effective region configured for reflecting the light incident on a surface (2) of the optically effective region. The reflective optical element (1) has an edge (4) forming at least part of a boundary of an edge-free surface (3) of the reflective optical element (1), wherein the edge-free surface (3) includes the surface (2) of the optically effective region. The edge (4) has a chamfer and/or a rounding. Also disclosed is a method for adapting a geometry of at least one surface region of a component of an optical arrangement, for example of a reflective optical element (1).

A reflector comprising a hollow body having an interior surface defining a passage through the hollow body, the interior surface having at least one optical surface part configured to reflect radiation and a supporter surface part, wherein the optical surface part has a predetermined optical power and the supporter surface part does not have the predetermined optical power. The reflector is made by providing an axially symmetric mandrel; shaping a part of the circumferential surface of the mandrel to form at least one inverse optical surface part that is not rotationally symmetric about the axis of the mandrel; forming a reflector body around the mandrel; and releasing the reflector body from the mandrel whereby the reflector body has an optical surface defined by the inverse optical surface part and a supporter surface part defined by the rest of the outer surface of the mandrel.

An optical diffraction component is configured to suppress at least one target wavelength by destructive interference. The optical diffraction component includes at least three diffraction structure levels that are assignable to at least two diffraction structure groups. A first of the diffraction structure groups is configured to suppress a first target wavelength λ.sub.1. A second of the diffraction structure groups is configured to suppress a second target wavelength λ.sub.2, where (λ.sub.1−λ.sub.2).sup.2/(λ.sub.1+λ.sub.2).sup.2<20%. A topography of the diffraction structure levels can be described as a superimposition of two binary diffraction structure groups. Boundary regions between adjacent surface sections of each of the binary diffraction structure groups have a linear course and are superimposed on one another at most along sections of the linear course.

A mirror arrangement (30) includes: a substrate (31) with a front side (31a) having a mirror face (32a) reflecting radiation (5), and a rear side (31b) facing away from the front side and on which at least one actuator (27) generating deformations of the mirror face is arranged. A water vapor (36)-sorbing material (33, 42) is formed on the rear side (31b) and forms an adhesive layer (33) for securing the actuator. The layer extends into interspaces (35) between the actuators (27). A surface (33a, 42a) of the water vapor-sorbing material is covered at least partly by a coating (37) which forms a water vapor diffusion barrier.