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: A recipe selection method includes obtaining measurements from metrology targets, metrology targets positioned on a semiconductor substrate, obtaining measurements from in-device targets, in-device targets positioned on the semiconductor substrate, and determining a recipe for accurate metrology using both metrology target measurements and in-device metrology measurements.

Abstract: Offline metrology measurements are performed on substrates that have been subjected to lithographic processing. Model parameters are calculated by fitting the measurements to an extended high-order substrate model defined using a combination of basis functions that include an edge basis function related to a substrate edge. A radial edge basis function may be expressed in terms of distance from a substrate edge. The edge basis function may, for example, be an exponential decay function or a rational function. Lithographic processing of a subsequent substrate is controlled using the calculated high-order substrate model parameters, in combination with low-order substrate model parameters obtained by fitting inline measurements to a low order model.

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: 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: 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.

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: 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: 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 vibration isolation system including a support, a forward actuator and a return device. The support is for supporting the body on a base. The support has a body engaging surface and a base engaging surface. The base engaging surface is arranged to couple to the base. The support couples the body engaging surface to the body in a coupled state. The support uncouples the body engaging surface from the body in an uncoupled state. The forward actuator moves the body and the body engaging surface together relatively to the base in a first direction from a first initial position to an end position in the coupled state. The return device is configured to move the body engaging surface relatively to the body opposite to the first direction from the end position to a second initial position in the uncoupled state.

Abstract: A method of topography determination, the method including: obtaining a first focus value derived from a computational lithography model modeling patterning of an unpatterned substrate or derived from measurements of a patterned layer on an unpatterned substrate; obtaining a second focus value derived from measurement of a substrate having a topography; and determining a value of the topography from the first and second focus values.

Abstract: An immersion lithographic apparatus having a fluid handling structure, the fluid handling structure configured to confine immersion fluid to a region and including: a meniscus controlling feature having an extractor exit on a surface of the fluid handling structure; and a gas knife system outwards of the extractor exit and including passages each having an exit, the passages having a plurality of first passages having a plurality of corresponding first exits on the surface, and a plurality of second passages having a plurality of corresponding second exits outwards of the first exits on the surface, wherein the surface faces and is substantially parallel to a top surface of a substrate during exposure, and the first exits and the second exits are arranged at a greater distance from the substrate than the extractor exit.

Abstract: A pellicle for a lithographic apparatus, the pellicle including nitridated metal silicide or nitridated silicon as well as a method of manufacturing the same. Also disclosed is the use of a nitridated metal silicide or nitridated silicon pellicle in a lithographic apparatus. Also disclosed is a pellicle for a lithographic apparatus including at least one compensating layer selected and configured to counteract changes in transmissivity of the pellicle upon exposure to EUV radiation as well as a method of controlling the transmissivity of a pellicle and a method of designing a pellicle.

Abstract: A method of determining a configuration of a projection system for a lithographic apparatus as an implementation of a quadratic programming problem with a penalty function. The method includes: receiving dependencies of one or more optical properties of the projection system on a configuration of a plurality of manipulators of the projection system; receiving a plurality of constraints which correspond to physical constraints of the manipulators; finding an initial configuration of the manipulators; and iteratively finding an output configuration of the manipulators. The iteration includes repeating the following steps: determining a set of the plurality of constraints that are violated; determining an updated configuration of the manipulators, the updated configuration of the manipulators being dependent on the set of the plurality of constraints that are violated and a penalty strength; and increasing the penalty strength. These steps are repeated until a convergence criterion is met.

Abstract: A patterning device cooling system for thermally conditioning a patterning device of a lithographic apparatus, wherein the patterning device in use, is being irradiated by exposure radiation, wherein the patterning device cooling system comprises: a thermal conditioner configured to thermally condition the patterning device; and a controller configured to control the thermal conditioner to thermally condition the patterning device dependent on an amount of the exposure radiation absorbed by the patterning device.

Abstract: A membrane assembly for EUV lithography, the membrane assembly including: a planar membrane; a border configured to hold the membrane; and a frame assembly connected to the border and configured to attach to a patterning device for EUV lithography, wherein the frame assembly is connected to the border in a direction perpendicular to the plane of the membrane such that in use the frame assembly is between the border and the patterning device.

Abstract: A method including: obtaining information regarding a patterning error in a patterning process involving a patterning device; determining a nonlinearity over a period of time introduced by modifying the patterning error by a modification apparatus according to the patterning error information; and determining a patterning error offset for use with the modification apparatus based on the determined nonlinearity.

Abstract: A lithographic apparatus that includes an illumination system that conditions a radiation beam, a first stationary plate having a first surface, and a reticle stage defining, along with the first stationary plate, a first chamber. The reticle stage supports a reticle in the first chamber, and the reticle stage includes a first surface spaced apart from a second surface of the first stationary plate, thereby defining a first gap configured to suppress an amount of contamination passing from a second chamber to the first chamber. The first stationary plate is between the reticle stage and both the illumination system and a projection system configured to project a pattern imparted to the radiation beam by the patterning device onto a substrate.

Abstract: Embodiments of a drain in a lithographic projection apparatus are described that have, for example, a feature which reduces inflow of gas into the drain during a period when no liquid is present in the drain. In one example, a passive liquid removal mechanism is provided such that the pressure of gas in the drain is equal to the ambient gas pressure and in another embodiment a flap is provided to close off a chamber during times when no liquid needs removing.

Abstract: Systems and methods of observing a sample in a multi-beam apparatus are disclosed. A multi-beam apparatus may comprise an array of deflectors configured to steer individual beamlets of multiple beamlets, each deflector of the array of deflectors having a corresponding driver configured to receive a signal for steering a corresponding individual beamlet. The apparatus may further include a controller having circuitry to acquire profile data of a sample and to control each deflector by providing the signal to the corresponding driver based on the acquired profile data, and a steering circuitry comprising the corresponding driver configured to generate a driving signal, a corresponding compensator configured to receive the driving signal and a set of driving signals from other adjacent drivers associated with adjacent deflectors and to generate a compensation signal to compensate a corresponding deflector based on the driving signal and the set of driving signals.