Abstract: In an immersion lithography apparatus or device manufacturing method, the position of focus of the projected image is changed during imaging to increase focus latitude. In an embodiment, the focus may be varied using the liquid supply system of the immersion lithographic apparatus.

Abstract: A lithographic apparatus includes a phase adjuster to adjust a phase of an optical wave traversing an optical element of the phase adjuster during exposure of a pattern on a substrate. In an embodiment, the optical element is a heat controllable optical element in a projection system of the lithographic apparatus. In use, the pattern is illuminated with an illumination mode including an off-axis radiation beam. This beam is diffracted into zeroth-order and first-order diffracted beams oppositely and asymmetrically inclined with respect to an optical axis. An area is identified where the first-order diffracted beam traverses the optical element. An image characteristic of an image of the pattern is optimized by calculating a desired optical phase of the first-order diffracted beam in relation to the optical phase of the zeroth-order diffracted beam. The phase adjuster is controlled to apply the desired optical phase to the first order diffracted beam.

Abstract: A spectral purity filter is configured to allow transmission therethrough of extreme ultraviolet (EUV) radiation and to refract or reflect non-EUV secondary radiation. The spectral purity filter may be part of a source module and/or a lithographic apparatus.

Abstract: System parameters are checked through self-assessment of a production wafer without a reference or a monitor wafer. In particular, exposure errors and substrate table positioning errors can be corrected for.

Abstract: A lithographic system is provided in which an extent of overlap between pattern sections is adjusted in order to match a size of a pattern section to a size of a repeating portion of the pattern to be formed.

Abstract: A device manufacturing method comprising applying patterns to a plurality of arrays of individually controllable elements, such that they modulate a beam of radiation, and projecting the modulated beam of radiation onto a substrate. The patterns applied to the arrays of individually controllable elements are arranged such that pre-determined amounts of background radiation are included in the modulated beam of radiation. The pre-determined amounts of background radiation being different for different locations on the arrays.

Abstract: A lithographic exposure process is performed on a substrate using a scanner. The scanner comprises several subsystems. There are errors in the overlay arising from the subsystems during the exposure. The overlay errors are measured using a scatterometer to obtain overlay measurements. Modeling is performed to separately determine from the overlay measurements different subsets of estimated model parameters, for example field distortion model parameters, scan/step direction model parameters and position/deformation model parameters. Each subset is related to overlay errors arising from a corresponding specific subsystem of the lithographic apparatus. Finally, the exposure is controlled in the scanner by controlling a specific subsystem of the scanner using its corresponding subset of estimated model parameters. This results in a product wafer being exposed with a well controlled overlay.

Abstract: A lithographic apparatus includes an illumination system configured to condition a radiation beam and a support constructed to support a patterning device. The patterning device is configured to form a patterned radiation beam. A substrate table is constructed to hold a substrate, and a projection system is configured to project the patterned radiation beam onto a target portion of the substrate. The apparatus includes a heater arrangement that includes an electron beam generator configured to generate an electron beam, and an electron beam guide arrangement configured to guide the electron beam onto an optical element of the lithographic apparatus. The optical element forms a part of the illumination system or the projection system which, in use, is traversed by the radiation beam. The heater arrangement is controllable to provide a distribution of heat on the optical element by deflection of the electron beam.

Abstract: Scatterometry for measuring overlay. A second set of superimposed gratings are superposed over a first set of superimposed gratings. The second set of gratings have a different periodicity from the first set of gratings or a different orientation. Consequently the first order diffraction pattern from the second set of superimposed gratings can be distinguished from the first order diffraction pattern from the first set of superimposed gratings.

Abstract: A mount configured to mount an optical element in a module for a lithographic apparatus. The mount includes a plurality of resilient members constructed and arranged to circumferentially support the optical element. Each resilient member includes a plurality of resilient subsections that are configured to engage the optical element around a perimeter thereof Each resilient subsection is configured to flex independent of another resilient subsection.

Abstract: A method controls scanning function of a lithographic apparatus. A monitor wafer is exposed to determine baseline control parameters pertaining to the scanning function. The baseline control parameters are retrieved from the monitor wafer. Parameter drift is determined from the baseline control parameters. Compensation is performed based on the determination. A different parameterization is used for control of the scanning control module than for communication between the scanning control module and the lithographic apparatus.

Abstract: A method produces at least one monitor wafer for a lithographic apparatus. The monitor wafer is for use in combination with a scanning control module to periodically retrieve measurements defining a baseline from the monitor wafer thereby determining parameter drift from the baseline. In doing this, allowance and/or correction can be to be made for the drift. The baseline is determined by initially exposing the monitor wafer(s) using the lithographic apparatus, such that the initial exposure is performed while using non-standard alignment model settings optimized for accuracy, such as those used for testing the apparatus. An associated lithographic apparatus is also disclosed.

Abstract: A lithographic apparatus includes a stage to hold an object, the stage being moveable relative to a reference structure in a motion range; a magnet structure to provide a spatially varying magnetic field in at least a part of the motion range, the magnet structure being moveable relative to the reference structure and the stage; a first position measurement system to provide a first measurement signal corresponding to a position of the stage and/or the object in a measurement direction relative to the reference structure; a second position measurement system to provide a second measurement signal corresponding to a position of the stage relative to the magnet structure; and a data processor to correct the first measurement signal with a value dependent on the second measurement signal to provide a corrected first measurement signal representative of the position of the stage and/or the object relative to the reference structure in the measurement direction.

Abstract: System parameters are checked through self-assessment of a production wafer without using a reference or a monitor wafer. In particular, the wafer is exposed at different orientations, the data from which provides for the calibration of system parameters.

Abstract: A method produces at least one monitor wafer for a lithographic apparatus. The monitor wafer is for use in combination with a scanning control module to periodically retrieve measurements defining a baseline from the monitor wafer, thereby determining parameter drift from the baseline. In doing this, allowance and/or correction can be to be made for the drift. The baseline is determined by initially exposing the monitor wafer(s) using the lithographic apparatus to perform multiple exposure passes on each of the monitor wafer(s). An associated lithographic apparatus is also disclosed.

Abstract: A protrusion is provided on a barrier member which at least partly confines a liquid between a projection system and a substrate. The protrusion is closer to the projection system than other parts of the barrier member to promote a meniscus of liquid to adhere between the protrusion and the projection system.

Abstract: A method of helping to prevent liquid reaching under a substrate is disclosed that includes introducing a gas at a bottom edge of the substrate so that a buffer is created at the edge of the substrate, helping to keep immersion liquid that is present at the top and edge of the substrate away from the bottom surface of the substrate.

Abstract: A lithographic apparatus is disclosed including a liquid supply system configured to at least partly fill a space between the projection system and the substrate with a liquid, an outlet configured to remove a mixture of liquid and gas passing through a gap between a liquid confinement structure of the liquid supply system and the substrate, and an evacuation system configured to draw the mixture through the outlet, the evacuation system having a separator tank arranged to separate liquid from gas in the mixture and a separator tank pressure controller, connected to a non-liquid-filled region of the separator tank, configured to maintain a stable pressure within the non-liquid-filled region.

Abstract: A beam modifying unit increases both temporal pulse length and Etendue of an illumination beam. The pulse modifying unit receives an input pulse of radiation and emits one or more corresponding output pulses of radiation. A beam splitter divides the incoming pulse into a first and a second pulse portion, and directs the first pulse portion along a second optical path and the second portion along a first optical path as a portion of an output beam. The second optical path includes a divergence optical element. A first and a second mirror, each with a radius of curvature, are disposed facing each other with a predetermined separation, and receive the second pulse portion to redirect the second portion, such that the optical path of the second portion through the pulse modifier is longer than that of the first portion, and the separation is less than radius of curvature.

Abstract: An imprint lithography apparatus is disclosed. The apparatus has a substrate table configured to support a lithographic substrate and a plurality of nozzles arranged to eject fluid onto the lithographic substrate, the plurality of nozzles extending over a distance which is substantially equal to or greater than a width of the substrate, wherein the nozzles, the lithographic substrate, or both, are moveable relative to the other.