Abstract: A charged particle assessment apparatus for detecting defects in samples by scanning a charged particle beam across a sample; the apparatus comprising: a detector unit configured to output a digital detection signal of pixel values in response to signal particles incident from the sample, the pixel values representing elongate pixels.

Abstract: An optical apparatus is disclosed, the apparatus comprising an optical element having a reflective surface for reflecting incident radiation in a beam path, and at least one sensor configured to sense radiation corresponding to a temperature of a respective portion of a backside surface of the optical element. Also disclosed is a method of controlling a temperature of a reflective surface of an optical element in a lithographic apparatus.

Abstract: The invention provides a wavelength tracking system comprising a wavelength tracking unit and an interferometer system. The wavelength tracking unit has reflection surfaces at stabile positions providing a first reflection path with a first path length and a second reflection path with a second path length. The first path length is substantially larger than the second path length.

Abstract: Apparatuses, systems, and methods for transferring fluid to a stage in a charged particle beam system are disclosed. In some embodiments, a stage may be configured to secure a wafer; a chamber may be configured to house the stage; and a tube may be provided within the chamber to transfer fluid between the stage and outside of the chamber. The tube may include a first tubular layer of first material, wherein the first material is a flexible polymer; and a second tubular layer of second material, wherein the second material is configured to reduce permeation of fluid or gas through the tube. In some embodiments, a system may include a degasser system outside of the chamber, where the degasser system may be configured to remove gases from the transfer fluid before the transfer fluid enters the tube.

Abstract: Systems directed to a stage apparatus in an electron beam inspection tool to inspect a sample are disclosed. The stage apparatus comprises a short stroke stage; a long stroke stage; a first sensor configured to measure a position of the short stroke stage with respect to a measurement reference; one or more roller bearings configured to support the long stroke stage; and a controller having circuitry and configured to control a motion of the long stroke stage and a motion of the short stroke stage for following movement of the reference at least partly based on measurement from the first sensor, wherein the controller is operable such that control of the long stroke stage is decoupled from the movement of the reference in at least a part of operation of the stage apparatus for reducing debris generation of the one or more roller bearings.

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 target arrangement comprising a first target region having at least a first pitch and at least a second pitch a second target region having at least a third pitch, wherein a portion of the first target region having a second pitch overlaps with a portion of the second target region.

Abstract: An optical source for a photolithography tool includes a source configured to emit a first beam of light and a second beam of light, the first beam of light having a first wavelength, and the second beam of light having a second wavelength, the first and second wavelengths being different; an amplifier configured to amplify the first beam of light and the second beam of light to produce, respectively, a first amplified light beam and a second amplified light beam; and an optical isolator between the source and the amplifier, the optical isolator including: a plurality of dichroic optical elements, and an optical modulator between two of the dichroic optical elements.

Abstract: Disclosed herein is an multi-array lens configured in use to focus a plurality of beamlets of charged particles along a multi-beam path, wherein each lens in the array comprises: an entrance electrode; a focusing electrode and a support. The focusing electrode is down beam of the entrance electrode along a beamlet path and is configured to be at a potential different from the entrance electrode. The support is configured to support the focusing electrode relative to the entrance electrode. The focusing electrode and support are configured so that in operation the lens generates a rotationally symmetrical field around the beamlet path.

Abstract: The invention provides an object holder to hold an object, comprising: a clamp side to clamp the object, wherein the clamp side is electrically conductive, at least one electrode arranged at a distance from the clamp side, and electrically isolated from the clamp side, a controller arranged to provide an electrode voltage to the at least one electrode based on a measured charge signal representative for a charge level of the object holder and/or the object in order to decrease a potential difference between an electrical potential of the clamp side and an electrical potential of the object.

Abstract: The disclosure relates to determining information about a target structure formed on a substrate using a lithographic process. In one arrangement, a cantilever probe is provided having a cantilever arm and a probe element. The probe element extends from the cantilever arm towards the target structure. Ultrasonic waves are generated in the cantilever probe. The ultrasonic waves propagate through the probe element into the target structure and reflect back from the target structure into the probe element or into a further probe element extending from the cantilever arm. The reflected ultrasonic waves are detected and used to determine information about the target structure.

Abstract: A radiation source for an EUV lithography apparatus is disclosed. The radiation source comprises a chamber comprising a plasma formation region, a radiation collector arranged in the chamber and configured to collect radiation emitted at the plasma formation region and to direct the collected radiation towards an intermediate focus region, and a radiation conduit disposed between the radiation collector and the intermediate focus region. The radiation conduit comprises at least one outlet on an inner surface of a wall of the radiation conduit for directing a protective gas flow, and at least one guide portion extending from the inner surface of the wall of the radiation conduit and configured to redirect the protective gas flow. Also disclosed is a method of reducing debris and/or vapor deposition in the radiation conduit by providing a protective gas flow to the at least one outlet of the radiation conduit.

Abstract: A multi-beam apparatus for observing a sample with high resolution and high throughput is proposed. In the apparatus, a source-conversion unit forms plural and parallel images of one single electron source by deflecting plural beamlets of a parallel primary-electron beam therefrom, and one objective lens focuses the plural deflected beamlets onto a sample surface and forms plural probe spots thereon. A movable condenser lens is used to collimate the primary-electron beam and vary the currents of the plural probe spots, a pre-beamlet-forming means weakens the Coulomb effect of the primary-electron beam, and the source-conversion unit minimizes the sizes of the plural probe spots by minimizing and compensating the off-axis aberrations of the objective lens and condenser lens.

Abstract: Disclosed herein is an apparatus comprising: a first electrically conductive layer, a second electrically conductive layer; a plurality of optics element s between the first electrically conductive layer and the second electrically conductive layer, wherein the plurality of optics elements are configured to influence a plurality of beams of charged particles; a third electrically conductive layer between the first electrically conductive layer and the second electrically conductive layer; and an electrically insulating layer physically connected to the optics elements, wherein the eclectically insulating layer is configured to electrically insulate the optics elements from the first electrically conductive layer, and the second electrically conductive layer.

Abstract: A scatterometer for measuring a property of a target on a substrate includes a radiation source, a detector, and a processor. The radiation source produces a radiated spot on the target. The scatterometer adjusts a position of the radiated spot along a first direction across the target and along a second direction that is at an angle with respect to the first direction. The detector receives radiation scattered by the target. The received radiation is associated with positions of the radiated spot on the target along at least the first direction. The detector generates measurement signals based on the positions of the radiated spot on the target. The processor outputs, based on the measurement signals, a single value that is representative of the property of the target. The processor also combines the measurement signals to output a combined signal and derives, based on the combined signal, the single value.

Abstract: Disclosed is an apparatus for and method of aligning a target composed of a target material and a conditioning beam provided to condition the target by changing the target's shape, mass distribution, etc., in which the conditioning beam includes structured light in the form of an inhomogeneous distribution of a propagation mode such as a polarization mode across a spatial mode of the target.

Abstract: A lithographic apparatus includes an illumination system to illuminate a pattern of a patterning device and a projection system to project an image of the pattern onto a substrate. The illumination system includes a first and second enclosures, a scaling device, and a protective device. The first enclosure encloses a first environment and includes a first opening and first connection corresponding to the first opening. The second enclosure includes a second connection structure to couple to the first connection structure to prevent mixing of substances between the first environment and a second environment outside of the first and second enclosures. The sealing device is disposed between the first and second connection structures. The material of the sealing device is chemically reactive to the first environment. The protective device is disposed on the sealing device proximal to the first environment to shield the sealing device from the first environment.

Abstract: A system includes optical devices, reflective devices, a movable reflective device, and a detector. The optical devices are disposed at a first plane and around a axis of the system and receive scattered radiation from targets. The reflective devices are disposed at at least a second plane and around the axis. Each of the reflective devices receives the scattered radiation from a corresponding one of the optical devices. The movable reflective device is disposed along the axis and receives the scattered radiation from each of the reflective devices. The detector receives the scattered radiation from the movable reflective device.

Abstract: Disclosed is a method of measuring a focus parameter from a focus target. and associated substrate and associated patterning device. The focus target comprises at least a first sub-target and a second sub-target, each having at least a periodic main feature, wherein a respective pitch and/or dimensional parameter of at least some sub-elements of the main feature are configured such that said first sub-target and second sub-target have a respective different best focus value; and wherein each said main feature is formed with a focus dependent center-of-mass and/or pitch. The method comprises obtaining a first measurement signal from said first sub-target and a second measurement signal from said second sub-target; determining a difference signal of said first measurement signal and second measurement signal; and determining said focus parameter from said difference signal.

Abstract: Disclosed among other aspects is a charged particle inspection system including a phaseplate configured and arranged to modify the local phase of charged particles in a beam to reduce the effects of lens aberrations. The phaseplate is made up of an array of apertures with the voltage and/or a degree of obscuration of the apertures being controlled individually or in groups.