An imprint lithography method of configuring an optical layer includes selecting one or more parameters of a nanolayer to be applied to a substrate for changing an effective refractive index of the substrate and imprinting the nanolayer on the substrate to change the effective refractive index of the substrate such that a relative amount of light transmittable through the substrate is changed by a selected amount.

An optical apparatus, which illuminates a first area with light from a light source while the first area is longer in a second direction intersecting a first direction than in the first direction, includes a collector optical member which is arranged in an optical path between the light source and the first area, and condenses the light from the light source to form a second area in a predetermined plane, the second area being longer in a fourth direction intersecting a third direction than in the third direction; and a first fly's eye optical member which is provided within the predetermined plane including the second area, and has a plurality of first optical elements guiding the light of the collector optical member to the first area.

Methods and apparatus for determining an intensity profile of a radiation beam. The method comprises providing a diffraction structure, causing a relative movement of the diffraction structure relative to the radiation beam from a first position, wherein the radiation beam does not irradiate the diffraction structure to a second position, wherein the radiation beam irradiates the diffraction structure, measuring, with a radiation detector, diffracted radiation signals produced from a diffraction of the radiation beam by the diffraction structure as the diffraction structure transitions from the first position to the second position or vice versa, and determining an intensity profile of the radiation beam based on the measured diffracted radiation signals.

An extreme ultraviolet light condensation mirror includes a substrate, and a multi-layer reflective film provided on the substrate, formed by alternately stacking an amorphous silicon layer and a layer having a refractive index different from a refractive index of the amorphous silicon layer, and configured to reflect extreme ultraviolet light, a layer on a most surface side in the multi-layer reflective film being the amorphous silicon layer containing a silicon atom bonded with a cyano radical.

There is provided an exposure apparatus including a first light shielding unit including a first light shielding member and a second light shielding member, which include end potions facing each other in a scanning direction and in which a relative distance therebetween in the scanning direction can be changed, and arranged at a position away from a conjugate plane of a surface to be illuminated to a side of a light source, and a second light shielding unit including a third light shielding member and a fourth light shielding member, which include end portions facing each other in the scanning direction and in which a relative distance therebetween in the scanning direction can be changed, and arranged at a position away from the conjugate plane to a side of the surface.

An illumination source apparatus (500), suitable for use in a metrology apparatus for the characterization of a structure on a substrate, the illumination source apparatus comprising: a high harmonic generation, HHG, medium (502); a pump radiation source (506) operable to emit a beam of pump radiation (508); and adjustable transformation optics (510) configured to adjustably transform the transverse spatial profile of the beam of pump radiation to produce a transformed beam (518) such that relative to the centre axis of the transformed beam, a central region of the transformed beam has substantially zero intensity and an outer region which is radially outwards from the centre axis of the transformed beam has a non-zero intensity, wherein the transformed beam is arranged to excite the HHG medium so as to generate high harmonic radiation (540), wherein the location of said outer region is dependent on an adjustment setting of the adjustable transformation optics.

An apparatus for receiving input radiation and broadening a frequency range of the input radiation to provide broadband output radiation. The apparatus includes a chamber, a fiber, a gas generating apparatus, and a radical generating apparatus. The fiber includes a hollow core configured to guide radiation propagating through the fiber, the hollow core in fluid communication with the chamber. The gas generating apparatus is configured to provide a gas within the chamber. The radical generating apparatus is configured to provide free radicals within the chamber to reduce contaminants in the gas. The apparatus may be included in a radiation source.

Treating a reflective optical element (104) for the EUV wavelength range that has a reflective coating on a substrate. The reflective optical element in a holder (106) is irradiated with at least one radiation pulse of a radiation source (102) having a duration of between 1 μs and 1 s. At least one radiation source (102) and the reflective optical element move relative to one another. Preferably, this is carried out directly after applying the reflective coating in a coating chamber (100). Reflective optical elements of this type are suitable in particular for use in EUV lithography or in EUV inspection of masks or wafers, for example.

An illumination optical system for projection lithography includes a pupil facet mirror having pupil facets. For at least some of the pupil facets which are designed as selectively reflecting pupil facets, the selectively reflecting pupil facet has a reflective coating for the illumination light, wherein a first coating area on a first part of the selectively reflecting pupil facet has a first reflectivity, a second coating area on a second part of the selectively reflecting pupil facet has a second reflectivity, the first coating area is different from the second coating area, and the first reflectivity is different from the second reflectivity. In combination or as an alternative, for at least some of the pupil facets which are designed as broadbands reflecting pupil facets, the broadband reflecting facets have a broadband reflective coating for the illumination light.

A multilayer stack in the form of a Bragg reflector comprising a graded interfacial layer and a method of manufacturing are disclosed. The graded interfacial layer eliminates the formation of low-reflectivity interfaces in a multilayer stack and reduces roughness of interfaces in a multilayer stack.