Abstract: A lithographic apparatus is provided that has a sensor at substrate level, the sensor including a radiation receiver, a transmissive plate supporting the radiation receiver, and a radiation detector, wherein the sensor is arranged to avoid loss of radiation between the radiation receiver and a final element of the radiation detector.

Abstract: Disclosed is a substrate comprising a combined target for measurement of overlay and focus. The target comprises: a first layer comprising a first periodic structure; and a second layer comprising a second periodic structure overlaying the first periodic structure. The target has structural asymmetry which comprises a structural asymmetry component resultant from unintentional mismatch between the first periodic structure and the second periodic structure, a structural asymmetry component resultant from an intentional positional offset between the first periodic structure and the second periodic structure and a focus dependent structural asymmetry component which is dependent upon a focus setting during exposure of said combined target on said substrate. Also disclosed is a method for forming such a target, and associated lithographic and metrology apparatuses.

Abstract: A method involving obtaining first calibration vibration data relating to vibrations of the lithographic apparatus from a sensor that is part of the lithographic apparatus and obtaining second calibration vibration data, the second calibration vibration data being a component of first parameter data of the lithographic apparatus. A filter is calculated from the first and second calibration vibration data, the filter being such that when applied to the first calibration vibration data, its output correlates closer with the second calibration vibration data. The filter can then be applied to vibration data obtained using the first sensor to obtain an estimate of a vibration component of the first parameter data during the lithographic process.

Abstract: A method of depositing an imprintable medium onto a target area of a substrate for imprint lithography is disclosed. The method includes moving the substrate, a print head comprising a nozzle to eject an imprintable medium onto the substrate, or both, relative to the other in a first direction across the target area while ejecting a first series of droplets of imprintable medium onto the substrate and moving the substrate, the print head, or both, relative to the other in a second opposing direction across the target area while ejecting a second series of droplets of imprintable medium onto the substrate on or adjacent to droplets from the first series of droplets.

Abstract: Causing a self-assemblable block copolymer (BCP) having first and second blocks to migrate from a region surrounding a lithography recess of the substrate and a dummy recess on the substrate to within the lithography recess and the dummy recess, causing the BCP to self-assemble into an ordered layer within the lithography recess, the layer having a first block domain and a second block domain, and selectively removing the first domain to form a lithography feature having the second domain within the lithography recess, wherein a width of the dummy recess is smaller than the minimum width required by the BCP to self-assemble, the dummy recess is within the region of the substrate surrounding the lithography recess from which the BCP is caused to migrate, and the width between portions of a side-wall of the lithography recess is greater than the width between portions of a side-wall of the dummy recess.

Abstract: A lithographic apparatus includes at least one image alignment sensor for receiving radiation projected from an alignment mark on a reticle. Processor processes signals from the sensor(s) to resolve spatial information in the projected alignment mark to establish a reference for measuring positional relationships between a substrate support and the patterning location. Examples of the sensor include line arrays of photodetectors. A single array can resolve spatial information in a plane of the sensor (X, Y direction) and in a perpendicular (Z) direction. At least a final step in establishing the reference position is performed while holding the substrate support stationary. Errors and delays induced by mechanical scanning of prior art sensors are avoided. Alternatively (not illustrated) the sensor is moved for mechanical scanning relative to the substrate support, independently of the main positioning systems.

Abstract: An imprint lithography template is provided with an alignment mark, wherein the alignment mark is formed from dielectric material having a refractive index which differs from the refractive index of the imprint lithography template, the dielectric material having a thickness which is such that it provides a phase difference between alignment radiation which has passed through the dielectric material and alignment radiation which has not passed through the dielectric material.

Abstract: In a lithographic projection apparatus, a liquid supply system maintains liquid in a space between the projection system and the substrate. The liquid supply system may further include a de-mineralizing unit, a distillation unit, a de-hydrocarbonating unit, a UV radiation source, and/or a filter configured to purify the liquid. A gas content reduction device may be provided to reduce a gas content of the liquid. A chemical may be added to the liquid using an adding device to inhibit lifeform growth and components of the liquid supply system may be made of a material which is non-transparent to visible light such that growth of lifeforms may be reduced.

Abstract: Disclosed herein is a computer-implemented method to improve a lithographic process for imaging a portion of a design layout onto a substrate using a lithographic projection apparatus and for transferring the imaged portion of the design layout to the substrate by an etching process, which includes the following steps: determining a value of at least one evaluation point of the lithographic process for each of a plurality of variations of the etching process; computing a multi-variable cost function of a plurality of design variables that are characteristics of the lithographic process, wherein the multi-variable cost function is a function of deviation from the determined values of the at least one evaluation point; and reconfiguring the characteristics of the lithographic process by adjusting the design variables until a termination condition is satisfied. This method may reduce the need of repeated adjustment to the lithographic process when the etching process varies.

Abstract: An illumination system is disclosed having a polarization member that includes first and second polarization modifiers movable into at least partial intersection with a radiation beam such that the respective polarization modifier applies a modified polarization to at least part of the beam. The illumination system further includes an array of individually controllable reflective elements positioned to receive the radiation beam after it has passed the polarization member, and a controller configured to control movement of the first and second polarization modifiers such that the first and second polarization modifiers intersect with different portions of the radiation beam.

Abstract: A position measurement system to determine a position of a first object relative to a second object, includes an encoder head mounted on the first object, a grating mounted on the second object, wherein the grating includes a first array of grating lines in a first direction and a second array of grating lines in a second direction to diffract a measurement beam incident on the first and second arrays in at least one first diffracted beam in the first direction and in at least one second diffracted beam in the second direction, wherein the first diffracted beam is for position measurement in the first direction and the second diffracted beam is for position measurement in the second direction, wherein the measurement beam has a power quantity, and the grating is configured to distribute the power quantity unevenly over the first and second diffracted beams.

Abstract: According to a first aspect of the present invention, there is provided a radiation source comprising: a reservoir configured to retain a volume of fuel; a nozzle, in fluid connection with the reservoir, and configured to direct a stream of fuel along a trajectory towards a plasma formation location; a laser configured to direct laser radiation at the stream at the plasma formation location to generate, in use, a radiation generating plasma; and a contamination filter assembly located in a fuel flow path of the radiation source, upstream of a nozzle outlet, a filter medium of that contamination filter assembly being held in place within the contamination filter assembly by a clamping force provided by one or more objects that at least partially surround the filter medium.

Abstract: A lithographic apparatus including a projection system configured to project a patterned radiation beam onto a substrate and a fluid confinement structure configured to confine immersion fluid in a localized region between a final element of the projection system and a surface of the substrate. The lithographic apparatus is configured to have a space bounded on one side by a surface of the projection system and/or a component of the lithographic apparatus at least partially surrounding the final element of the projection system, and on the other side by a surface of the fluid confinement structure. The apparatus is configured to increase the humidity of the gas within the space.

Abstract: A lithographic apparatus includes a first object holder and a second object holder. The first object holder is arranged to hold an object at a holder-facing surface. The object has the holder-facing surface. The second object holder is arranged to hold the object at the holder-facing surface. The lithographic apparatus is arranged to deform a contaminating particle at the holder-facing surface more when the object is held at the second object holder than when the object is held at the first object holder.

Abstract: A method of modifying a lithographic apparatus comprising an illumination system for providing a radiation beam, a support structure for supporting a patterning device to impart the radiation beam with a pattern in its cross-section, a first lens for projecting the radiation beam at the patterning device with a first magnification, a substrate table for holding a substrate, and a first projection system for projecting the patterned radiation beam at a target portion of the substrate with a second magnification. The first lens and the first projection system together provide a third magnification. The method comprises reducing by a first factor the first magnification to provide a second lens for projecting the radiation beam with a fourth magnification; and increasing by the first factor the second magnification to provide a second projection system for projecting the patterned radiation beam at the target portion of the substrate with a fifth magnification.

Abstract: An apparatus and method for cleaning a contaminated surface of a lithographic apparatus are provided. A liquid confinement structure comprises at least two openings used to supply and extract liquid to a gap below the structure. The direction of flow between the openings can be switched. Liquid may be supplied to the gap radially outward of an opening adapted for dual flow. Supply and extraction lines to respectively supply liquid to and extract liquid from the liquid confinement structure have an inner surface that is resistant to corrosion by an organic liquid. A corrosive cleaning fluid can be used to clean photo resist contamination.

Abstract: A liquid confinement system for use in immersion lithography is disclosed in which the meniscus of liquid between the liquid confinement system and the substrate is pinned substantially in place by a meniscus pinning feature. The meniscus pinning feature comprises a plurality of discrete outlets arranged in a polygonal shape.

Abstract: A substrate distortion measurement apparatus comprising one or more optical detectors arranged to measure the locations of pits or holes provided in a substrate, a memory arranged to store previously determined locations of the pits or holes in the substrate, and a comparator arranged to compare the measured locations of the pits or holes with the previously determined locations of the pits or holes, to determine distortion of the substrate.

Abstract: A method of selecting a periodic modulation to be applied to a variable of a radiation source, wherein the source delivers radiation for projection onto a substrate and wherein there is relative motion between the substrate and the radiation at a scan speed, the method including: for a set of system parameters and for a position on the substrate, calculating a quantity, the quantity being a measure of the contribution to an energy dose delivered to the position that arises from the modulation being applied to the variable of the source, wherein the contribution to the energy dose is calculated as a convolution of: a profile of radiation, and a contribution to an irradiance of radiation delivered by the source; and selecting a modulation frequency at which the quantity for the set of system parameters and the position on the substrate satisfies a certain criteria.

Abstract: A fuel supply for an EUV radiation source is disclosed. The fuel supply comprises a reservoir (40) for retaining a volume of fuel (42), a nozzle (32), in fluid connection with the reservoir, and configured to direct a stream of fuel along a trajectory towards a plasma formation location, and a fuel contamination control arrangement (44) which separates contamination particles from the fuel. The contamination control arrangement comprises at least one acoustic filter. The acoustic filter may apply an acoustic standing wave to the fuel. Also disclosed is a method of controlling contamination in such a fuel supply.