Abstract: The present disclosure proposes an anti-rotation lens and using it as an anti-rotation condenser lens in a multi-beam apparatus with a pre-beamlet-forming mechanism. The anti-rotation condenser lens keeps rotation angles of beamlets unchanged when changing currents thereof, and thereby enabling the pre-beamlet-forming mechanism to cut off electrons not in use as much as possible. In this way, the multi-beam apparatus can observe a sample with high resolution and high throughput, and is competent as a yield management tool to inspect and/or review defects on wafers/masks in semiconductor manufacturing industry.

Abstract: Disclosed is a bandwidth calculation system for determining a desired wavelength bandwidth for a measurement beam in a mark detection system, the bandwidth calculation system comprising a processing unit configured to determine the desired wavelength bandwidth based on mark geometry information, e.g. comprising mark depth information representing a depth of a mark. In an embodiment the desired wavelength bandwidth is based on a period and/or a variance parameter of a mark detection error function. The invention further relates to a mark detection system, a position measurement system and a lithographic apparatus comprising the bandwidth calculation system, as well as a method for determining a desired wavelength bandwidth.

Abstract: An apparatus and method to determine a property of a substrate by measuring, in the pupil plane of a high numerical aperture lens, an angle-resolved spectrum as a result of radiation being reflected off the substrate. The property may be angle and wavelength dependent and may include the intensity of TM- and TE-polarized radiation and their relative phase difference.

Abstract: An improved charged particle beam inspection apparatus, and more particularly, a particle beam inspection apparatus for detecting a thin device structure defect is disclosed. An improved charged particle beam inspection apparatus may include a charged particle beam source to direct charged particles to a location of a wafer under inspection over a time sequence. The improved charged particle beam apparatus may further include a controller configured to sample multiple images of the area of the wafer at difference times over the time sequence. The multiple images may be compared to detect a voltage contrast difference or changes to identify a thin device structure defect.

Abstract: A method includes: producing a light beam made up of pulses having a wavelength in the deep ultraviolet range, each pulse having a first temporal coherence defined by a first temporal coherence length and each pulse being defined by a pulse duration; for one or more pulses, modulating the optical phase over the pulse duration of the pulse to produce a modified pulse having a second temporal coherence defined by a second temporal coherence length that is less than the first temporal coherence length of the pulse; forming a light beam of pulses at least from the modified pulses; and directing the formed light beam of pulses toward a substrate within a lithography exposure apparatus.

Abstract: Focus metrology patterns and methods are disclosed which do not rely on sub-resolution features. Focus can be measured by measuring asymmetry of the printed pattern (T), or complementary pairs of printed patterns (TN/TM). Asymmetry can be measured by scatterometry. Patterns may be printed using EUV radiation or DUV radiation. A first type of focus metrology pattern comprises first features (422) interleaved with second features (424) A minimum dimension (w1) of each first feature is close to a printing resolution. A maximum dimension (w2) of each second feature in the direction of periodicity is at least twice the minimum dimension of the first features. Each first feature is positioned between two adjacent second features such that a spacing (w1?) and its nearest second feature is between one half and twice the minimum dimension of the first features. A second type of focus metrology pattern comprises features (1122, 1124) arranged in pairs.

Abstract: In a lithographic process in which a series of substrates are processed in different contexts, object data (such as performance data representing overlay measured on a set of substrates that have been processed previously) is received. Context data represents one or more parameters of the lithographic process that vary between substrates within the set. By principal component analysis or other statistical analysis of the performance data, the set of substrates are partitioned into two or more subsets. The first partitioning of the substrates and the context data are used to identify one or more relevant context parameters, being parameters of the lithographic process that are observed to correlate most strongly with the first partitioning. The lithographic apparatus is controlled for new substrates by reference to the identified relevant context parameters. Embodiments with feedback control and feedforward control are described.

Abstract: A method to improve a lithographic process for imaging a portion of a design layout onto a substrate using a lithographic projection apparatus having an illuminator and projection optics, the method including: computing a multi-variable cost function of a plurality of design variables that are characteristics of the lithographic process, at least some of the design variables being characteristics of the illumination produced by the illuminator and of the design layout, wherein the multi-variable cost function is a function of a three-dimensional resist profile on the substrate, or a three-dimensional radiation field projected from the projection optics, or both; and reconfiguring one or more characteristics of the lithographic process by adjusting the design variables until a predefined termination condition is satisfied.

Abstract: A plate to be positioned between a movable stage and a projection system of a lithographic apparatus, the plate having a surface to face the movable stage; an opening through the plate for passage of patterned radiation beam; one or more gas outlets in a side of the opening and in the surface of the plate, wherein the one or more gas outlets are configured to supply gas to a region between the movable stage and the projection system, wherein all of the one or more gas outlets in the surface of the plate are positioned such that, for each of such one or more gas outlets, a line that is both orthogonal to the surface and intersects the gas outlet does not intersect the patterning device at any point during the entire range of movement of the patterning device.

Abstract: A component for use in a patterning device environment including a patterning device, wherein the component is treated to suppress EUV plasma-induced contaminant release and/or atomic hydrogen or other radicals induced defectivity. A conduit array comprising at least one conduit, wherein the at least one conduit has been treated to promote adhesion of a contaminant to the at least one conduit.

Abstract: Online calibration of laser performance as a function of the repetition rate at which the laser is operated is disclosed. The calibration can be periodic and carried out during a scheduled during a non-exposure period. Various criteria can be used to automatically select the repetition rates that result in reliable in-spec performance. The reliable values of repetition rates are then made available to the scanner as allowed values and the laser/scanner system is then permitted to use those allowed repetition rates.

Abstract: A method, and associated apparatus and computer program, to determine corrections for a parameter of interest, such as critical dimension, of a patterning process. The method includes determining an exposure control correction for an exposure control parameter and, optionally, determining a process control correction for a process control parameter, based upon a measurement of the parameter of interest of a structure, and an exposure control relationship and a process control relationship. The exposure control relationship describes the dependence of the parameter of interest on the exposure control parameter and the process control relationship describes the dependence of the parameter of interest on the process control parameter. The exposure control correction and process control correction may be co-optimized to minimize variation of the parameter of interest of subsequent exposed and processed structures relative to a target parameter of interest.

Abstract: Systems and methods for conducting charged particle beam modulation are disclosed. According to certain embodiments, a charged particle beam apparatus generates a plurality of charged particle beams. A modulator may be configured to receive the plurality of charged particle beams and generate a plurality of modulated charged particle beams. A detector may be configured to receive the plurality of modulated charged particle beams.

Abstract: An illumination source apparatus (500), suitable for use in a metrology apparatus for the characterization of a structure on a substrate, the illumination source apparatus comprising: a high harmonic generation, HHG, medium (502); a pump radiation source (506) operable to emit a beam of pump radiation (508); and adjustable transformation optics (510) configured to adjustably transform the transverse spatial profile of the beam of pump radiation to produce a transformed beam (518) such that relative to the centre axis of the transformed beam, a central region of the transformed beam has substantially zero intensity and an outer region which is radially outwards from the centre axis of the transformed beam has a non-zero intensity, wherein the transformed beam is arranged to excite the HHG medium so as to generate high harmonic radiation (540), wherein the location of said outer region is dependent on an adjustment N setting of the adjustable transformation optics.

Abstract: One modified source-conversion unit and one method to reduce the Coulomb Effect in a multi-beam apparatus are proposed. In the modified source-conversion unit, the aberration-compensation function is carried out after the image-forming function has changed each beamlet to be on-axis locally, and therefore avoids undesired aberrations due to the beamlet tilting/shifting. A Coulomb-effect-reduction means with plural Coulomb-effect-reduction openings is placed close to the single electron source of the apparatus and therefore the electrons not in use can be cut off as early as possible.

Abstract: A calibration method for calibrating the position error in the point of interest induced from the stage of the defect inspection tool is achieved by controlling the deflectors directly. The position error in the point of interest is obtained from the design layout database.

Abstract: Disclosed is a method for reconstructing a parameter of a lithographic process. The method comprises the step of designing a preconditioner suitable for an input system comprising the difference of a first matrix and a second matrix, the first matrix being arranged to have a multi-level structure of at least three levels whereby at least two of said levels comprise a Toeplitz structure. One such preconditioner is a block-diagonal matrix comprising a BTTB structure generated from a matrix-valued inverse generating function. A second such preconditioner is determined from an approximate decomposition of said first matrix into one or more Kronecker products.

Abstract: A method for determining a characteristic of a feature in an object, the feature being disposed below a surface of the object is disclosed. The surface of the object is irradiated with a pulsed pump radiation beam so as to produce an acoustic wave in the object. The surface of the object is then irradiated with a measurement radiation beam. A portion of the measurement radiation beam scattered from the surface is received and a characteristic of the feature in the object is determined from at least a portion of the measurement radiation beam scattered from the surface within a measurement time period. A temporal intensity distribution of the pulsed pump radiation beam is selected such that in the measurement time period a signal to background ratio is greater than a signal to background ratio achieved using a single pulse of the pulsed pump radiation beam.

Abstract: The present disclosure relates to lithographic apparatuses and processes, and more particularly to tools for optimizing illumination sources and masks for use in lithographic apparatuses and processes. According to certain aspects, the present disclosure significantly speeds up the convergence of the optimization by allowing direct computation of gradient of the cost function. According to other aspects, the present disclosure allows for simultaneous optimization of both source and mask, thereby significantly speeding the overall convergence. According to still further aspects, the present disclosure allows for free-form optimization, without the constraints required by conventional optimization techniques.

Abstract: The disclosure relates to measuring a target. In one arrangement, a measurement apparatus is provided that has an optical system configured to illuminate a target with radiation and direct reflected radiation from the target to a sensor. A programmable spatial light modulator in a pupil plane of the optical system is programmed to redirect light in each of a plurality of pupil plane zones in such a way as to form a corresponding plurality of images at different locations on the sensor. Each image is formed by radiation passing through a different respective one of the pupil plane zones.