Abstract: A beam homogenizer for homogenizing a beam of radiation and an illumination system and metrology apparatus comprising such a beam homogenizer as provided. The beam homogenizer comprises a filter system having a controllable radial absorption profile and configured to output a filtered beam and an optical mixing element configured to homogenize the filtered beam. The filter system may be configured to homogenize the angular beam profile radially and said optical mixing element may be configured to homogenize the angular beam profile azimuthally.

Abstract: A lithographic projection apparatus, including a liquid supply system configured to supply a liquid to a space between a projection system and a movable table; a member to at least partly confine liquid in the space, the member including a recovery opening facing toward the movable table, the recovery opening including a first porous structure configured to recover fluid; and a chamber configured to receive recovered fluid and to separate liquid from gas in the recovered fluid, the chamber including a second porous structure.

Abstract: An electrostatic clamp (300) and a method for manufacturing the same is disclosed. The electrostatic clamp includes a first layer (302) having a first ultra-low expansion (ULE) material, a second layer (304) coupled to the first layer, having a second ULE material, and a third layer (306), coupled to the second layer, having a third ULE material. The electrostatic clamp further includes a plurality of fluid channels (316) located between the first layer and the second layer and a composite layer (308) interposed between the second layer and the third layer. The method for manufacturing the electrostatic clamp includes forming the plurality of fluid channels, disposing the composite layer on the third layer, and coupling the third layer to the second layer. The plurality of fluid channels is configured to carry a thermally conditioned fluid for temperature regulation of a clamped object.

Abstract: A patterning device support (200), for example, a patterning device (202) or substrate support, can be configured to release internal stresses of a patterning device loaded thereon. The patterning device support can include a positive pressuring generating interface (206a, 206b) or an acoustic vibration generating interface (206a, 206b), or can be configured to oscillate while at least a portion of patterning device is decoupled from the patterning device support. A method of transferring a patterning device between a patterning device handling apparatus and a patterning device support configured to move the patterning device can include positioning the patterning device onto a surface of the patterning device support, and performing a process that releases internal stress of the patterning device.

Abstract: An alignment sensor for a lithographic apparatus is arranged and constructed to measure an alignment of a movable part of the lithographic apparatus in respect of a stationary part of the lithographic apparatus. The alignment sensor comprises a light source configured to generate a pulse train at a optical wavelength and a pulse repetition frequency, a non-linear optical element, arranged in an optical propagation path of the pulse train, the non-linear optical element configured to transform the pulse train at the optical wavelength into a transformed pulse train in an optical wavelength range, an optical imaging system configured to project the transformed pulse train onto an alignment mark comprising a diffraction grating; a detector to detect a diffraction pattern as diffracted by the diffraction grating, and a data processing device configured to derive alignment data from the detected diffraction pattern as detected by the detector.

Abstract: A substrate support, includes: a substrate support location configured to support a substrate, and a vacuum clamping device configured to clamp the substrate on the substrate support location, wherein the vacuum clamping device includes at least one reduced pressure source to create a reduced pressure, at least one vacuum section connected to the at least one reduced pressure source, wherein the at least one vacuum section is configured to attract the substrate towards the substrate support location, and a control device configured to control a spatial pressure profile along the at least one vacuum section with which the substrate is attracted by the vacuum clamping device, wherein the control device includes a substrate shape data input to receive substrate shape data representing shape data of the substrate to be clamped, and wherein the control device is configured to adapt the spatial pressure profile in dependency of the substrate shape data.

Abstract: A patterning device support for controlling a temperature of a patterning device can include a movable component. The movable component can include a gas inlet for supplying a gas flow across a surface of the patterning device and a gas outlet for extracting the gas flow. The patterning device support can also include a gas flow generator coupled to a duct, for recirculating the gas flow from the gas outlet to the gas inlet.

Abstract: An apparatus (AS) measures positions of marks (202) on a lithographic substrate (W). An illumination arrangement (940, 962, 964) provides off-axis radiation from at least first and second regions. The first and second source regions are diametrically opposite one another with respect to an optical axis (O) and are limited in angular extent. The regions may be small spots selected according to a direction of periodicity of a mark being measured, or larger segments. Radiation at a selected pair of source regions can be generated by supplying radiation at a single source feed position to a self-referencing interferometer. A modified half wave plate is positioned downstream of the interferometer, which can be used in the position measuring apparatus. The modified half wave plate has its fast axis in one part arranged at 45° to the fast axis in another part diametrically opposite.

Abstract: An objective lens system having a high numerical aperture, a large working distance, and low optical aberrations over a wide spectral band of wavelengths is disclosed. The objective lens system includes a first lens group, a second lens group, and a third lens group. The first lens group includes first and second positive meniscus lenses that are positioned at a distance from each other along an optical axis of the objective lens system. The distance may be dependent on a focal length of the objective lens system. The second lens group includes first and second meniscus lenses and a bi-convex lens. The third lens group includes a bi-concave lens and a doublet lens.

Abstract: A system and method that bends a reticle and senses a curvature of a bent reticle in real-time. The system includes movable reticle stage, reticle vacuum clamps, sensor systems, and reticle bender. The reticle bender comprises piezo actuators. The sensor systems comprises measurement targets and corresponding sensors. The sensors are attached to the movable reticle stage and the measurement targets are attached to the reticle clamps, the reticle bender, or on reticle surfaces. The system is configured to determine a width of the reticle or distance between measurement targets at opposing ends of the reticle, measure a first rotational angle at a first end of the reticle, and measure a second local rotational angle at a second end of the reticle that is opposite to the first end. Based on the width or distance and the first and second angles, a field curvature of the reticle is determined.

Abstract: A patterning device support (1100) for controlling a temperature of a patterning device (1102) can include a movable component (1104). The movable component can include a gas inlet (1108) for supplying a gas flow across a surface of the patterning device and a gas outlet (1110) for extracting the gas flow. The patterning device support can also include a gas flow generator (1118) coupled to a duct (1114, 1116) for recirculating the gas flow from the gas outlet to the gas inlet.

Abstract: A system for controlling temperature of a patterning device in a lithographic apparatus is discussed. The system includes a patterning device support configured to support a patterning device and a reticle cooling system configured to provide substantially uniform temperature distribution across the patterning device. The reticle cooling system includes a first and second array of gas inlets configured to provide a first and second gas flow along a first and second direction across a surface of the patterning device, respectively, where first and second directions are opposite to each other. The reticle cooling system further includes a switching control system configured to control operation of the first and second arrays of gas inlets.

Abstract: An apparatus (AS) measures positions of marks (202) on a lithographic substrate (W). An illumination arrangement (940, 962, 964) provides off-axis radiation from at least first and second regions. The first and second source regions are diametrically opposite one another with respect to an optical axis (O) and are limited in angular extent. The regions may be small spots selected according to a direction of periodicity of a mark being measured, or larger segments. Radiation at a selected pair of source regions can be generated by supplying radiation at a single source feed position to a self-referencing interferometer. A modified half wave plate is positioned downstream of the interferometer, which can be used in the position measuring apparatus. The modified half wave plate has its fast axis in one part arranged at 45° to the fast axis in another part diametrically opposite.

Abstract: A system and method are provided for determining deformation of a patterning device and/or shift position of the patterning device relative. The system includes a first sensing sub-system that measures respective positions of a plurality of reference marks on the patterning device, and a second sensing sub-system that measures positions of the edge of the patterning device relative to the support. The system further includes a controller to determine an absolute position of the patterned portion and change in the absolute position based on measured respective positions of marks on the patterning device, determine a change in a relative position of the edge of the patterned device based on the measured edge positions, and estimate a change in a position of the patterning device relative to the support and a change in a pattern distortion of the patterned portion of the patterning device over a time period.

Abstract: An objective lens system having a high numerical aperture, a large working distance, and low optical aberrations over a wide spectral band of wavelengths is disclosed. The objective lens system includes a first lens group, a second lens group, and a third lens group. The first lens group includes first and second positive meniscus lenses that are positioned at a distance from each other along an optical axis of the objective lens system. The distance may be dependent on a focal length of the objective lens system. The second lens group includes first and second meniscus lenses and a bi-convex lens. The third lens group includes a bi-concave lens and a doublet lens.

Abstract: An objective lens system having a high numerical aperture, a large working distance, and low optical aberrations over a wide spectral band of wavelengths is disclosed. The objective lens system includes a first lens group, a second lens group, and a third lens group. The first lens group includes first and second positive meniscus lenses that are positioned at a distance from each other along an optical axis of the objective lens system. The distance may be dependent on a focal length of the objective lens system. The second lens group includes first and second meniscus lenses and a bi-convex lens. The third lens group includes a bi-concave lens and a doublet lens.

Abstract: Apparatus, systems, and methods are used for detecting the alignment of a feature on a substrate using a polarization independent interferometer. The apparatus, system, and methods include optical elements that receive light that has diffracted or scattered from a mark on a substrate. The optical elements may split the diffracted light into multiple subbeams of light which are detected by one or more detectors. The diffracted light may be combined optically or during processing after detection. The system may determine alignment and/or overlay based on the received diffracted light having any polarization angle or state.

Abstract: An inspection apparatus may determine precise OV measurements of a target on a substrate using an optical pupil symmetrizer to reduce the inspection apparatus's sensitivity to asymmetry and non-uniformity of the illumination beam in the pupil plane. The inspection apparatus includes an illumination system that forms a symmetrical illumination pupil by (1) splitting an illumination beam into sub-beams, (2) directing the sub-beams along different optical branches, (3) inverting or rotating at least one of the sub-beams in two dimensions, and recombining the sub-beams along the illumination path to symmetrize the intensity distribution. The illumination system is further configured such that the first and second sub-beams have an optical path difference that is greater than a temporal coherence length of the at least one light source and less than a depth of focus in the pupil plane of the objective optical system.

Abstract: A fluid proximity sensor for surface measurements having a measurement chamber (210) with a measurement nozzle (205), a reference chamber (220) with a reference nozzle (225), and a diaphragm (215) forming an interface between the reference chamber and the measurement chamber. A shroud (280) that encloses the measurement nozzle and reference nozzle provides a peripheral gap (295) between the shroud and a work surface (290) being measured. By connecting either a partial vacuum supply or a partial fluid supply to the shroud, the internal shroud pressure can be raised or lowered and thus the gain-frequency operating regime of the proximity sensor optimized. Movement of the diaphragm in response to differential pressure changes can be sensed by optical, capacitive or inductive means (275).

Abstract: A deformable optical device includes a reflection device having a first reflecting surface and a second surface, an actuator (e.g., an integrated circuit piezoelectric actuator) having a support device and moveable extensions extending therefrom, which are coupled to the second surface, and electrodes coupled to corresponding ones of the extensions. Wavefront aberrations are detected and used to generate a control signal. The extensions are moved based on the control signal. The movement deforms the reflecting surface to correct the aberrations in the wavefront.