Abstract: An illumination system for a lithographic apparatus comprises a radiation intensity filter for controlling the intensity distribution of a beam of radiation travelling along an optical axis (Z), the radiation intensity filter comprising a first member and a second member. Each of the first and second members comprise a plurality of opaque regions which are substantially opaque to the radiation beam. The first member and second member are moveable relative to one another between a first relative position and a second relative position. In the first relative position at least a portion of one of the opaque regions of the first member overlaps in the direction of the optical axis with a portion of one of the opaque regions of the second member. In the second relative position the total area of overlap in the direction of the optical axis of the opaque regions of the first member with the opaque regions of the second member is less than that in the first relative position.

Abstract: An imprint lithography method is provided. The method includes undertaking first and second imprints, which comprises for each imprint: for an area of a substrate provided with a plurality of drops of imprintable medium in respectively first and second configurations, imprinting a pattern in the imprintable medium using a same imprint template, pockets being formed between the drops of the imprintable medium, the imprint template and the substrate during the imprinting of the pattern, wherein the first configuration of drops of imprintable medium is different from the second configuration of drops of imprintable medium, such that pockets formed during the second imprint are formed at different locations relative to the imprint template to pockets formed during the first imprint.

Abstract: An immersion lithographic projection apparatus is disclosed in which liquid is provided between a projection system of the apparatus and a substrate. The use of both liquidphobic and liquidphilic layers on various elements of the apparatus is provided to help prevent formation of bubbles in the liquid and to help reduce residue on the elements after being in contact with the liquid.

Abstract: Methods, computer program products and apparatuses for optimizing design rules for producing a mask are disclosed, while keeping the optical conditions (including but not limited to illumination shape, projection optics numerical aperture (NA) etc.) fixed. A cross-correlation function is created by multiplying the diffraction order functions of the mask patterns with the eigenfunctions from singular value decomposition (SVD) of a TCC matrix. The diffraction order functions are calculated for the original design rule set, i.e., using the unperturbed condition. ILS is calculated at an edge of a calculated image of a critical polygon using the cross-correlation results and using translation properties of a Fourier transform. Once an optimum separation is calculated, it is incorporated into the design rule to optimize the mask layout for improved ILS throughout the mask.

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 method of measuring aberration present in a lithographic apparatus comprising the following steps. Modulating a radiation beam using a reflective patterning device. Projecting the radiation beam using a projection system. Detecting the projected radiation using a sensor. Measuring aberration via interference in the detected radiation beam. The radiation beam is tilted away from the optical axis of the projection system prior to entering the projection system.

Abstract: A method of determining a defect in a grid plate of an encoder-type position measurement system, the method including providing an encoder-type position measurement system to measure a position of a movable object with respect to another object, the encoder-type position measurement system including a grid plate and an encoder head, measuring a quantity of light reflected on each of the two or more detectors, using a combined light intensity of the reflected light on the two or more detectors to determine a reflectivity signal representative for the reflectivity of the grid plate at the measurement location, and determining a presence of a defect at the measurement location on the basis of the reflectivity signal of the grid plate.

Abstract: An imprint lithography alignment apparatus is disclosed that includes at least two detectors which are configured to detect an imprint template alignment mark, wherein the alignment apparatus further comprises alignment radiation adjustment optics which are configured to provide adjustment of locations from which the at least two alignment detectors receive alignment radiation.

Abstract: A system is configured to measure two separately polarized beams upon diffraction from a substrate in order to determine properties of a grating on a substrate. Linearly polarized light sources are passed via a fixed phase retarder in order to change the phase of one of two orthogonally polarized radiation beams with respect to the other of the two beams. The relative phases of the two radiation beams and other features of the beams as measured in a detector gives rise to properties of the substrate surface. The grating and the initial linear polarization of the radiation beam are angled non-orthogonally relative to each other.

Abstract: The present invention relates generally to methods and apparatuses for test pattern selection for computational lithography model calibration. According to some aspects, the pattern selection algorithms of the present invention can be applied to any existing pool of candidate test patterns. According to some aspects, the present invention automatically selects those test patterns that are most effective in determining the optimal model parameter values from an existing pool of candidate test patterns, as opposed to designing optimal patterns. According to additional aspects, the selected set of test patterns according to the invention is able to excite all the known physics and chemistry in the model formulation, making sure that the wafer data for the test patterns can drive the model calibration to the optimal parameter values that realize the upper bound of prediction accuracy imposed by the model formulation.

Abstract: A method controls a scanning function of a lithographic apparatus. A first alignment strategy is used. A monitor wafer is exposed to determine baseline control parameters pertaining to the scanning function. The baseline control parameters are periodically retrieved from the monitor wafer. Parameter drift is determined from the baseline control parameters. Corrective action is taken based on the determination. A production wafer is exposed using a second alignment strategy, different to the first alignment strategy. The corrective action is modified so as to be substantially closer to the correction that would have been made had the second alignment strategy been used in exposing the monitor wafer.

Abstract: A lithographic apparatus is disclosed that includes an encoder type sensor system configured to measure a position of a substrate table of the lithographic apparatus relative to a reference structure. The encoder type sensor system includes an encoder sensor head and an encoder sensor target and the lithographic apparatus comprises a recess to accommodate the encoder sensor target.

Abstract: A lithographic projection apparatus is disclosed in which measures are taken to prevent or reduce the presence of bubbles in liquid through which the projection beam radiates. This may be done, for example, by ensuring that a gap between a substrate and a substrate table is filled with immersion liquid or by causing a localized flow radially outwardly from the optical axis in the vicinity of the edge of the substrate.

Abstract: A lithographic apparatus includes a source configured to generate a radiation beam comprising desired radiation and undesired radiation using a plasma, an illumination system configured to condition the radiation beam and to receive hydrogen gas during operation of the lithographic apparatus, and a support structure constructed to hold a patterning device. The patterning device is capable of imparting the radiation beam with a pattern in its cross-section 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 lithographic apparatus is configured such that the radiation beam on entering the projection system includes at least 50% of the undesired radiation that is generated by the plasma and includes wavelengths of radiation that interact with the hydrogen gas to generate hydrogen radicals.

Abstract: An imprint lithography apparatus is disclosed. The apparatus includes an electromagnetic Lorentz actuator arrangement configured to move an imprint template arrangement, the electromagnetic Lorentz actuator arrangement comprising: an array of magnets; and an array of conductors, each conductor configured to carry an electric current, one of the array of magnets or the array of conductors being moveable and connected to the imprint template arrangement, and the other of the array of magnets or the array of conductors extending at least partially around or forming a part of a substrate holder; the array of magnets and the array of conductors together being in a configuration which facilitates moving of the moveable one of the array of magnets or the array of conductors in six degrees of freedom, such that the imprint template arrangement is also movable in six degrees of freedom.

Abstract: An electromagnetic actuator includes a first and second magnetic members that are displaceable relative to each other and are arranged to provide a magnetic circuit; and a coil configured to, in use, receive a current to generate a magnetic flux through the magnetic circuit, thereby generating a force between the first and second magnetic members in a first direction, the magnetic flux, in use, being transferred between the first and second magnetic members through a first surface of the first magnetic member and a second surface of the second magnetic member, the first and second surface being separated by an airgap, wherein the first surface and the second surface are arranged relative to each other such that an outer dimension of the first surface extends beyond an outer dimension of the second surface in a second direction substantially perpendicular to the first direction.

Abstract: During a multiple patterning process every nth element of the pattern is removed. The removal of the elements of the patterns happens after the pattern has been printed into the radiation sensitive material or etched into substrate. Advantageously, the original mask is not varied, and another exposure step is used to remove the elements of the pattern.

Abstract: A method of calculating process corrections for a lithographic tool, and associated apparatuses. The method comprises measuring process defect data on a substrate that has been previously exposed using the lithographic tool; fitting a process signature model to the measured process defect data, so as to obtain a model of the process signature for the lithographic tool; and using the process signature model to calculate the process corrections for the lithographic tool.

Abstract: A lithographic apparatus for patterning a beam of radiation and projecting it onto a substrate, comprising at least two spectral purity filters configured to reduce the intensity of radiation in the beam of radiation in at least one undesirable range of radiation wavelength, wherein the two spectral purity filters are provided with different radiation filtering structures from each other.

Abstract: The measurement of two separately polarized beams (Ix, Iy) upon diffraction from a substrate (W) in order to determine properties of the substrate is disclosed. Circularly or elliptically polarized radiation is passed via a variable phase retarder in order to change the phase of one of two orthogonally polarized radiation beams with respect to the other of the two beams. The phase change is dependent on the wavelength of the polarized beam. The relative phases of the two radiation beams and other features of the beams as measured in a detector gives rise to properties of the substrate surface.