An EUV reflective structure includes a substrate and multiple pairs of a Si layer and a Mo layer. The Si layer includes a plurality of cavities.

Beam guiding devices for guiding a laser beam, in particular in a direction towards a target region for producing extreme ultraviolet (EUV) radiation, include an adjustment device for adjusting a beam diameter and an aperture angle of the laser beam. The adjustment device includes a first mirror having a first curved reflecting surface, a second mirror having a second curved reflecting surface, a third mirror having a third curved reflecting surface, a fourth mirror having a fourth curved reflecting surface, and a movement device configured to adjust the beam diameter and the aperture angle of the laser beam by moving the first reflecting surface and the fourth reflecting surface relative to one another and, independently thereof, moving the second reflecting surface and the third reflecting surface together relative to the first reflecting surface and the fourth reflecting surface.

A mirror, in particular for a microlithographic projection exposure apparatus, has an optically effective surface (10a), a mirror substrate (11) and a reflection layer stack (12) configured to reflect electromagnetic radiation that is incident on the optically effective surface. A metallic diffusion barrier layer (13) is arranged on that side of the reflection layer stack which faces toward the optically effective surface, and a stabilization layer (14) is arranged on the side of the diffusion barrier layer that faces toward the optically effective surface (10a). The stabilization layer reduces deformation of the diffusion barrier layer compared to an analogous structure without such a stabilization layer upon irradiation of the optically effective surface with electromagnetic radiation. The stabilization layer has a porosity, a relative density of which is no more than 80%, where the relative density is defined as the ratio between geometric density and true density.

An EUV collector mirror has a reflection surface (16) to reflect usable EUV light which impinges on the reflection surface (16) from a source region (17) to a subsequent EUV optics. The reflection surface (16) carries a pump light grating structure (19) configured to retroreflect pump light (22) which impinges upon the pump light grating structure (19) from the source region (17) back to the source region (17). The pump light (22) has a wavelength deviating from the wavelength of the usable EUV light. Such EUV collector mirror enables a high conversion efficiency between the energy of pump light of a laser discharged produced plasma (LDPP) EUV light source on the one hand and the resulting usable EUV energy on the other.

Systems and methods described herein relate to the manufacture of optical elements and optical systems. An example system may include an optical component configured to direct light from a light source to illuminate a photoresist material at a desired angle and to expose at least a portion of an angled structure in the photoresist material, where the photoresist material overlays at least a portion of a top surface of a substrate. The optical component includes a container containing an light-coupling material that is selected based in part on the desired angle. The optical component also includes a mirror arranged to reflect at least a portion of the light to illuminate the photoresist material at the desired angle.

A modular light assembly for an ultraviolet (UV) treatment device includes a UV light reflective surface. First and second sidewalls are coupled to respective sides of the reflective surface. Electrical input contacts are formed on each of the first and second sidewalls for receiving electrical power, and electrical output contacts are formed on each of the first and second sidewalls for delivering electrical power. A plurality of UV lamps are included, each of which have a first end and a second end. The first end of each of the UV lamps is coupled to a respective one of the electrical output contacts on the first sidewall, and the second end is coupled to a respective one of the electrical output contacts on the second sidewall.

Extreme ultraviolet (EUV) mask blanks, methods for their manufacture and production systems therefor are disclosed. The EUV mask blanks comprise a substrate; a multilayer stack of reflective layers on the substrate; a capping layer on the multilayer stack of reflecting layers; and an absorber layer on the capping layer, the absorber layer made from amorphous tantalum nitride formed by non-reactive sputtering.

A multilayer film structure, and method of making such a multilayer film structure, which includes a first layer consisting essentially of a first material and a second layer consisting essentially of a second material. In embodiments, the multilayer film structure includes a plurality of first layers alternating with a plurality of second layers. The layers are constructed by applying a N.sub.2-based reactive sputtering methodology so that the layers maintain a largely amorphous microstructure and a stable and high reflectivity upon annealing at temperatures up to 800° C. for 1 hour.

A method and apparatus for cleaning vacuum ultraviolet (VUV) optics (e.g., one or more mirrors of a VUV) of a substrate inspection system is disclosed. The cleaning system ionizes or disassociates hydrogen gas in a VUV optics environment to generate hydrogen radicals (e.g., H*) or ions (e.g., H.sup.+, H.sub.2.sup.+, H.sub.3.sup.+, which remove water or hydrocarbons from the surface of the one or more mirrors. The one or more VUV mirrors may include a reflective material, such as aluminum. The one or more VUV mirrors may have a protective coating to protect the reflective material from any detrimental reaction to the hydrogen radicals or ions. The protective coating may include a noble metal.

The disclosure provides a method that includes filling a cavity in a substrate with a second material, wherein the substrate includes a first material. The method also includes using galvanic and/or chemical deposition of a third material to apply an overcoating to a first surface of the substrate in a region of the cavity. The method further includes removing the second material from the cavity. In addition, the method includes, before or after removing the second material from the cavity, applying a reflective layer to the overcoating. The disclosure also provides related optical articles and systems.