Abstract: An encoder includes an optical component and an enclosing device having a first surface portion and a second surface portion. The first surface portion is arranged to receive from an ambient environment a first radiation beam. The second surface portion is arranged to receive from the ambient environment a second radiation beam. The optical component is arranged to combine the first and second radiation beams. The enclosing device is arranged to propagate the first radiation beam along a first path. The first path is between the first surface portion and the optical component. The enclosing device is arranged to propagate the second radiation beam along a second path. The second path is between the second surface portion and the optical component. The enclosing device is arranged to enclose a space, so as to isolate the first path and the second path from the ambient environment.

Abstract: A lithographic apparatus with a cover plate formed separately from a substrate table and means for stabilizing a temperature of the substrate table by controlling the temperature of the cover plate is disclosed. A lithographic apparatus with thermal insulation provided between a cover plate and a substrate table so that the cover plate acts as a thermal shield for the substrate table is disclosed. A lithographic apparatus comprising means to determine a substrate table distortion and improve position control of a substrate by reference to the substrate table distortion is disclosed.

Abstract: Disclosed is an inspection apparatus for use in lithography. It comprises a support for a substrate carrying a plurality of metrology targets; an optical system for illuminating the targets under predetermined illumination conditions and for detecting predetermined portions of radiation diffracted by the targets under the illumination conditions; a processor arranged to calculate from said detected portions of diffracted radiation a measurement of asymmetry for a specific target; and a controller for causing the optical system and processor to measure asymmetry in at least two of said targets which have different known components of positional offset between structures and smaller sub-structures within a layer on the substrate and calculate from the results of said asymmetry measurements a measurement of a performance parameter of the lithographic process for structures of said smaller size. Also disclosed are substrates provided with a plurality of novel metrology targets formed by a lithographic process.

Abstract: A lithographic projection apparatus is disclosed in which a liquid supply system provides a liquid between the projection system and the substrate. An active drying station is provided to actively remove the liquid from the substrate W or other objects after immersion of all or part of a surface of the substrate W or other objects.

Abstract: A method comprising determining aberrations caused by each lithographic apparatus of a set of lithographic apparatuses, calculating adjustments of the lithographic apparatuses which minimize differences between the aberrations caused by each of the lithographic apparatuses, and applying the adjustments to the lithographic apparatuses, providing better matching between the aberrations of patterns projected by the lithographic apparatuses.

Abstract: An illumination system for a metrology apparatus that can achieve illumination spatial profile flexibility, high polarization extinction ratio, and high contrast. The illumination system includes a polarizing beam splitter (PBS), an illumination mode selector (IMS), and a reflective spatial light modulator (SLM). The PBS divides an illumination beam into sub-beams. The IMS has a plurality of apertures that transmits at least one sub-beam and may be arranged in multiple illumination positions corresponding to illumination modes. A pixel array of the reflective SLM and reflects a portion of the sub-beam transmitted by the IMS back to the IMS and PBS. The PBS, IMS, SLM collectively generates a complex amplitude or intensity spatial profile of the transmitted sub-beam.

Abstract: Disclosed herein is a computer-implemented method for determining an overlapping process window (OPW) of an area of interest on a portion of a design layout for a device manufacturing process for imaging the portion onto a substrate, the method including: obtaining a plurality of features in the area of interest; obtaining a plurality of values of one or more processing parameters of the device manufacturing process; determining existence of defects, probability of the existence of defects, or both in imaging the plurality of features by the device manufacturing process under each of the plurality of values; and determining the OPW of the area of interest from the existence of defects, the probability of the existence of defects, or both.

Abstract: A lithographic apparatus includes a number of sensors for measuring positions of features on a substrate prior to applying a pattern. Each sensor includes an imaging optical system. Position measurements are extracted from pixel data supplied by an image detector in each sensor. The imaging optical system includes one or more light field modulating elements and the processor processes the pixel data as a light-field image to extract the position measurements. The data processor may derive from each light-field image a focused image of a feature on the substrate, measuring positions of several features simultaneously, even though the substrate is not at the same level below all the sensors. The processor can also include corrections to reduce depth dependency of an apparent position of the feature include a viewpoint correction. The data processor can also derive measurements of heights of features on the substrate.

Abstract: A method including providing a plurality of unit cells for a plurality of gauge patterns appearing in one or more images of one or more patterning process substrates, each unit cell representing an instance of a gauge pattern of the plurality of gauge patterns, averaging together image information of each unit cell to arrive at a synthesized representation of the gauge pattern, and determining a geometric dimension of the gauge pattern based on the synthesized representation.

Abstract: 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.

Abstract: In a lithographic process, product units such as semiconductor wafers are subjected to lithographic patterning operations and chemical and physical processing operations. Alignment data or other measurements are made at stages during the performance of the process to obtain object data representing positional deviation or other parameters measured at points spatially distributed across each unit. This object data is used to obtain diagnostic information by performing a multivariate analysis to decompose a set of vectors representing the units in the multidimensional space into one or more component vectors. Diagnostic information about the industrial process is extracted using the component vectors. The performance of the industrial process for subsequent product units can be controlled based on the extracted diagnostic information.

Abstract: Disclosed is a metrology apparatus for use in a lithographic manufacturing process. The metrology apparatus comprises a radiation source comprising a drive laser having an output split into a plurality of optical paths, each comprising a respective broadband light generator. The metrology apparatus further comprises illumination optics for illuminating a structure, at least one detection system for detecting scattered radiation, having been scattered by the structure and a processor for determining a parameter of interest of the structure from the scattered radiation.

Abstract: An EUV source for generating a beam of EUV radiation, has a droplet generator with a nozzle assembly to emit droplets of fuel from a nozzle towards a plasma formation location. The nozzle assembly receives the fuel from a reservoir. The nozzle assembly has a pump chamber receiving the fuel from the reservoir and an actuator to vibrate a membrane that forms a wall of the pump chamber. The wall is oriented perpendicularly to a direction wherein the nozzle emits the fuel. The nozzle assembly has first and second nozzle filters non-adjacently arranged in series in a path of the fuel from the pump chamber to the nozzle.

Abstract: A method of measuring a parameter of a device manufacturing process is disclosed. The method includes measuring a target on a substrate by illuminating the target with measurement radiation and using an optical apparatus to detect the measurement radiation scattered by the target. The target has a target structure having a first periodic component and a second periodic component. The optical apparatus receives radiation resulting from diffraction of the measurement radiation from the target structure. The received radiation includes at least one diffraction order that would not be received from diffraction of the measurement radiation from the first periodic component alone nor from diffraction of the measurement radiation from the second periodic component alone.

Abstract: Methods of measuring a target formed by a lithographic process, a metrology apparatus and a polarizer assembly are disclosed. The polarizer assembly comprises a polarizing structure having a substantially planar form and configured to polarize radiation passing there through in a circular polarizing region. The circular polarizing region is configured to apply a first polarization to radiation passing through a first one of two pairs of diametrically opposite quadrants of the circular polarizing region and to apply a second polarization, orthogonal to the first polarization, to radiation passing through a second one of two pairs of diametrically opposite quadrants of the circular polarizing region.

Abstract: A lithographic apparatus comprising a projection system configured to project a patterned radiation beam to form an exposure area on a substrate held on a substrate table, the lithographic apparatus further comprising a cooling apparatus for cooling the substrate, wherein the cooling apparatus comprises a cooling element located above the substrate table and adjacent to the exposure area, the cooling element being configured to remove heat from the substrate.

Abstract: In the measurement of properties of a wafer substrate, such as Critical Dimension or overlay a sampling plan is produced 2506 defined for measuring a property of a substrate, wherein the sampling plan comprises a plurality of sub-sampling plans. The sampling plan may be constrained to a predetermined fixed number of measurement points and is used 2508 to control an inspection apparatus to perform a plurality of measurements of the property of a plurality of substrates using different sub-sampling plans for respective substrates, optionally, the results are stacked 2510 to at least partially recompose the measurement results according to the sample plan.

Abstract: A measurement method comprising using multiple radiation poles to illuminate a diffraction grating on a mask at a mask side of a projection system of a lithographic apparatus, coupling at least two different resulting diffraction orders per illumination pole through the projection system, using the projection system to project the diffraction orders onto a grating on a wafer such that a pair of combination diffraction orders is formed by diffraction of the diffraction orders, coupling the combination diffraction orders back through the projection system to detectors configured to measure the intensity of the combination diffraction orders, and using the measured intensity of the combination diffraction orders to measure the position of the wafer grating.

Abstract: In immersion lithography after exposure of a substrate is complete, a detector is used to detect any residual liquid remaining on the substrate and/or substrate table.

Abstract: In a dark-field metrology method using a small target, a characteristic of an image of the target, obtained using a single diffraction order, is determined by fitting a combination fit function to the measured image. The combination fit function includes terms selected to represent aspects of the physical sensor and the target. Some coefficients of the combination fit function are determined based on parameters of the measurement process and/or target. In an embodiment the combination fit function includes jinc functions representing the point spread function of a pupil stop in the imaging system.