Abstract: A table for a lithographic apparatus, the table having an encoder plate located on the table, a gap between the encoder plate and a top surface of the table, the gap located radially inward of the encoder plate relative to the periphery of the table, and a fluid extraction system with an opening in the surface of the gap to extract liquid from the gap.

Abstract: A substrate table to support a substrate on a substrate supporting area, the substrate table having a heat transfer fluid channel at least under the substrate supporting area, and a plurality of heaters and/or coolers to thermally control the heat transfer fluid in the channel at a location under the substrate supporting area.

Abstract: A method of measuring a target, an associated lithographic method, an associated computer program product and an associated litho cell is provided, wherein the method includes measuring the target subsequent to exposure of structures by a lithographic process in a current layer on a substrate over one or more preceding layers, wherein the one or more preceding layers have each undergone an etch step, and wherein the target is only in at least one of the one or more preceding layers. In this way, an after-etch measurement of the target can be obtained.

Abstract: A method for unloading a substrate from a support table configured to support the substrate, the method including: supplying gas to a gap between a base surface of the support table and the substrate via a plurality of gas flow openings in the support table, wherein during an initial phase of unloading the gas is supplied through at least one gas flow opening in an outer region of the support table and not through any gas flow opening in a central region of the support table radially inward of the outer region, and during a subsequent phase of unloading the gas is supplied through at least one gas flow opening in the outer region and at least one gas flow opening in the central region.

Abstract: A lithographic apparatus including: a projection system to project radiation onto a substrate supported on a substrate stage, during an exposure phase; a sensing system to sense a property of the substrate on the stage during a sensing phase; and a positioning system to determine a position of the stage relative to a reference system via a radiation path between the stage and the reference system, wherein the apparatus is configured to control stage movement relative to the reference system in the sensing phase and to control other movement relative to the reference system during the exposure phase; the stage or reference system having an outlet to provide a gas curtain to reduce ingress of ambient gas into the path; and the apparatus is operative such that a characteristic of the gas curtain is different in at least part of the sensing phase compared to in the exposure phase.

Abstract: A method for determining a mechanical property of a layer applied to a substrate and associated control system for controlling a lithographic process. The method includes obtaining measured out-of-plane deformation of the substrate, the out-of-plane deformation including deformation normal to a substrate plane defined by, or parallel to, a substrate surface. The measured out-of-plane deformation is fitted to a second order polynomial in two coordinates associated with the substrate plane and the mechanical property (e.g. anisotropic Young's moduli) of the layer is determined based on characteristics of the fitted second order polynomial. The mechanical property of the layer can be used to calibrate an in-plane distortion model of the substrate for predicting in-plane distortion based on the measured out-of-plane deformation.

Abstract: A difficulty of contamination interfering with a grid plate positional measurement system is addressed. In one embodiment contamination is prevented from coming into contact with the grating or the sensor. In an embodiment, surface acoustic waves are used to detach contamination from a surface of the grating or sensor.

Abstract: A three-dimensional mask model that provides a more realistic approximation of the three-dimensional effects of a photolithography mask with sub-wavelength features than a thin-mask model. In one embodiment, the three-dimensional mask model includes a set of filtering kernels in the spatial domain that are configured to be convolved with thin-mask transmission functions to produce a near-field image. In another embodiment, the three-dimensional mask model includes a set of correction factors in the frequency domain that are configured to be multiplied by the Fourier transform of thin-mask transmission functions to produce a near-field image.

Abstract: A method and apparatus to measure overlay from images of metrology targets, images obtained using acoustic waves, for example images obtained using an acoustic microscope. The images of two targets are obtained, one image using acoustic waves and one image using optical waves, the edges of the images are determined and overlay between the two targets is obtained as the difference between the edges of the two images.

Abstract: A substrate handling system for handling a substrate, the substrate handling system including a holder for holding the substrate, a rotation device for rotating the holder around an axis perpendicular to a plane, and a mover for moving the holder along a path in the plane relative to the axis. Further, there is provided a lithographic apparatus including the substrate handling system. The substrate handling system may include a coupling device arranged to couple the holder to the mover or the rotation device in a first situation. The coupling device may be arranged to decouple the holder from the mover or rotation device in a second situation.

Abstract: Disclosed are a method, computer program and a metrology apparatus for measuring a process effect parameter relating to a manufacturing process for manufacturing integrated circuits on a substrate. The method comprises determining for a structure, a first quality metric value for a quality metric from a plurality of measurement values each relating to a different measurement condition while cancelling or mitigating for the effect of the process effect parameter on the plurality of measurement values and a second quality metric value for the quality metric from at least one measurement value relating to at least one measurement condition without cancelling or mitigating for the effect of the process effect parameter on the at least one measurement value. The process effect parameter value for the process effect parameter can then be calculated from the first quality metric value and the second quality metric value, for example by calculating their difference.

Abstract: A reflector for EUV radiation, the reflector comprising a reflector substrate and a reflective surface, the reflector substrate having a plurality of coolant channels formed therein, the coolant channels being substantially straight, substantially parallel to each other and substantially parallel to the reflective surface and configured so that coolant flows in parallel through the coolant channels and in contact with the reflector substrate.

Abstract: An electron source, e.g. for a free electron laser used for EUV lithography comprises: a cathode (203) configured to be connected to a negative potential (100, 101); a laser (110) configured to direct pulses of radiation onto the cathode so as to cause the cathode to emit bunches of electrons; an RF booster (180) connected to an RF source and configured to accelerate the bunches of electrons; and a timing corrector (303, 313, 400, 401) configured to correct the time of arrival of bunches of electrons at the RF booster relative to the RF voltage provided by the RF source. The timing corrector may comprise a correction electrode (303, 313) surrounding a path of the bunches of electrons from the cathode to the RF booster and a correction voltage source (400, 401) configured to apply a correction voltage to the correction electrode.

Abstract: A lithographic projection apparatus includes a support structure to hold a patterning device, the patterning device configured to pattern a beam of radiation according to a desired pattern; a projection system to project the patterned beam onto a target portion of a substrate; a substrate table configured to hold the substrate, the substrate table including a support surface to support an intermediary plate between the projection system and at least one of the substrate and an object positioned on the substrate table and not in contact with the at least one of the substrate and the object; and a liquid supply system to provide a liquid, through which the beam is to be projected, in a space between the projection system and the at least one of the substrate and the object.

Abstract: A method for improving a lithographic process for imaging a portion of a design layout onto a substrate using a lithographic projection apparatus, the method including: calculating a discrete pupil profile based on a desired pupil profile; selecting a discrete change to the discrete pupil profile; and applying the selected discrete change to the discrete pupil profile. The methods according to various embodiments disclosed herein may reduce the computational cost of discrete optimization from O(an) to O(n) wherein a is constant and n is the number of knobs that can generate discrete change in the pupil profile.

Abstract: A substrate table to support a substrate, the substrate table including a main body, burls extending from the main body and having first upper ends that define a support surface to support the substrate, and support pins having second upper ends. The support pins are movable between a retracted position and an extended position. The support pins are arranged to support the substrate in the extended position. The support pins are arranged to be switched to a first stiffness mode and a second stiffness mode. In the first stiffness mode, the support pins have a first stiffness in a direction parallel to the support surface. In the second stiffness mode, the support pins have a second stiffness in the direction parallel to the support surface. The first stiffness is different from the second stiffness.

Abstract: A measurement system for a lithographic apparatus includes a sub-frame compliantly mounted on a reference frame. A measurement device, e.g. an alignment sensor, is mounted on the sub-frame. Soft mounting of the sub-frame isolates the alignment sensor from high-frequency disturbances, e.g. acoustic noise, by acting as a low-pass filter with a cut-off frequency, e.g. in the range of from 100 to 200 Hz.

Abstract: An immersion lithographic apparatus is provided having a substrate table including a drain configured to receive immersion fluid which leaks into a gap between an edge of a substrate on the substrate table and an edge of a recess in which the substrate is located. A thermal conditioning system is provided to thermally condition at least the portion of the recess supporting the substrate by directing one or more jets of fluid onto a reverse side of the section supporting the substrate.

Abstract: A temperature conditioning system for a lithographic apparatus. Temperature variations in an object cause object deformation which prevents the object being accurately positioned. Temperature condition systems use conduit systems, provided with fluid, in or on the object to control the temperature of the object to reduce object deformation. In this way, parts of the object can be more accurately positioned. However, acceleration of the object and the temperature conditioning system induces variation in pressure within the fluid inside the conduit system on or in the object, which may also cause object deformation. To provide an improved conduit system, the lithographic apparatus further includes a control system which is used to control the movement of the object based on measurements indicating pressure variation in the conduit.

Abstract: A lithographic apparatus including a fluid handling structure configured to contain immersion fluid in a space adjacent to an upper surface of the substrate table and/or a substrate located in a recess of the substrate table, a cover having a planar main body that, in use, extends around a substrate from the upper surface to a peripheral section of an upper major face of the substrate in order to cover a gap between an edge of the recess and an edge of the substrate, and an immersion fluid film disruptor, configured to disrupt the formation of a film of immersion fluid between an edge of the cover and immersion fluid contained by the fluid handling structure during movement of the substrate table relative to the fluid handling structure.