Systems and methods for reducing the buildup of charge during the investigation of samples using charged particle beams, according to the present disclosure include irradiating a first portion of a sample during a first time period, wherein the irradiating the first portion of the sample causes a gradual accumulation of net charge in the first portion of the sample, generating imaging data based on emissions resultant from irradiating the first portion of the sample, and then irradiating a second portion of a sample holder for a second time period. The methods may further includes iteratively repeating the irradiation of the first portion and the second portion during imaging of the sample region. When more than one region of interest on the sample is to be investigated, the method may also include continuing to image additional portions of the sample by iteratively irradiating a region of interest on the sample and a corresponding portion of the sample holder.

A multi-beam electron-optical system for a charged-particle assessment tool, the system comprising: a plurality of control lenses, a plurality of objective lenses and a controller. The plurality of control lenses are configured to control a parameter of a respective sub-beam. The plurality of objective lenses are configured to project one of the plurality of charged-particle beams onto a sample. The controller controls the control lenses and the objective lenses so that the charged particles are incident on the sample with a desired landing energy, demagnification and/or beam opening angle.

A particle beam system includes: a particle source to generate a beam of charged particles; a first multi-lens array including a first multiplicity of individually adjustable and focusing particle lenses so that at least some of the particles pass through openings in the multi-lens array in the form of a plurality of individual particle beams; a second multi-aperture plate including a multiplicity of second openings downstream of the first multi-lens array so that some of the particles which pass the first multi-lens array impinge on the second multi-aperture plate and some of the particles which pass the first multi-lens array pass through the openings in the second multi-aperture plate; and a controller configured to supply an individually adjustable voltage to the particle lenses of the first multi-lens array and thus individually adjust the focusing of the associated particle lens for each individual particle beam.

Apparatuses, systems, and methods for multi-modal operations of a multi-beam inspection system are disclosed. An apparatus for generating multi-modal beamlets may include an aperture array which includes a first group of apertures having a first size and a second group of apertures having a second size different from the first size, the second group of apertures adjoining the first group of apertures, in which the first group of apertures and the second group of apertures are in different pass-or-block statuses. A multi-beam apparatus of multi-modal inspection operations may include the aforementioned apparatus, a source configured to emit charged particles, a condenser system configured to set a projection area of the charged particles, and circuitry for controlling the first and second groups of apertures.

An electrostatic device includes a top and a bottom silicon layer, around an insulating buried layer. A beam opening allows a beam of charged particles to travel through. The device is encapsulated in an insulating layer. One or more electrodes and ground planes are deposited on the insulating layer. These also cover the inside of the beam opening. Electrodes and ground planes are physically and electrically separated by micro-trenches and micro-undercuts that provide shadow areas when the conductive areas are deposited. Electrodes may be shaped as elongated islands and may include portions overhanging the top silicon layer, supported by electrode-anchors. Manufacturing starts from a single wafer including the top, buried, and bottom layers, or it starts from two separate silicon wafers. Manufacturing includes steps to form the top and bottom beam openings and microstructures, to encapsulate the device in an insulating layer, and to deposit electrodes and ground areas.

An observation apparatus and method that avoids drawbacks of a Lorentz method and observes a weak scatterer or a phase object with in-focus, high resolution, and no azimuth dependency, by a Foucault method observation using a hollow-cone illumination that orbits and illuminates an incident electron beam having a predetermined inclination angle, an electron wave is converged at a position (height) of an aperture plate downstream of a sample, and a bright field condition in which a direct transmitted electron wave of the sample passes through the aperture plate, a dark field condition in which the transmitted electron wave is shielded, and a Schlieren condition in which approximately half of the transmitted wave is shielded as a boundary condition of both of the above conditions are controlled, and a spatial resolution of the observation image is controlled by selecting multiple diameters and shapes of the opening of the aperture plate.

A charged particle buncher includes a series of spaced apart electrodes arranged to generate a shaped electric field. The series includes a first electrode, a last electrode and one or more intermediate electrodes. The charged particle buncher includes a waveform device attached to the electrodes and configured to apply a periodic potential waveform to each electrode independently in a manner so as to form a quasi-electrostatic time varying potential gradient between adjacent electrodes and to cause spatial distribution of charged particles that form a plurality of nodes and antinodes. The nodes have a charged particle density and the antinodes have substantially no charged particle density, and the nodes and the antinodes are formed from a charged particle beam configured to hit the target.

Electron beam modulation in response to optical pump pulses applied to a sample is measured using SPAD elements. Individual detection events are used to form histograms of numbers of events in time bins associated with pump pulse timing. The histograms can be produced at a SPAD array, simplifying data transfer. In some examples, two SPAD arrays are stacked and a coincidence circuit discriminates signal events from noise events by determining corresponding events are detected withing a predetermined time window.

In one embodiment, a multi charged particle beam writing apparatus includes a blanking aperture array substrate provided with a plurality of blankers configured to respectively perform blanking deflection on a plurality of charged particle beams included in a multi-beam, and a first shield member which is disposed downstream of the blanking aperture array substrate with respect to a travel direction of the multi-beam, has a cylindrical part in which the multi-beam passes through, and is composed of a high magnetic permeability material.

A method of performing x-ray spectroscopy surface material analysis of a region of interest of a sample with an evaluation system that includes a scanning electron microscope (SEM) column, an x-ray detector and an x-ray polarizer, comprising: positioning a sample within a field of view of the scanning electron microscope; generating an electron beam having a landing energy about equal to an ionization energy of the materials within the region of interest of the sample; scanning the region of interest with the electron beam set to collide with the sample thereby generating x-rays emitted from near a surface of the sample, the x-rays including characteristic x-rays and Bremsstrahlung radiation; and detecting x-rays generated while the region of interest is scanned by the electron after the x-rays pass through the x-ray polarizer that blocks a higher percentage of the Bremsstrahlung radiation than the characteristic x-rays.