The disclosure relates to apparatus and methods for manipulating charged particle beams. In one arrangement, an aperture assembly is provided that comprises a first aperture body and a second aperture body. Apertures in the first aperture body are aligned with apertures in the second aperture body. The alignment allows charged particle beams to pass through the aperture assembly. The first aperture body comprises a first electrode system for applying an electrical potential to an aperture perimeter surface of each aperture in the first aperture body. The first electrode system comprises a plurality of electrodes. Each electrode is electrically isolated from each other electrode and electrically connected simultaneously to the aperture perimeter surfaces of a different one of a plurality of groups of the apertures in the first aperture body.

A detector substrate (or detector array) for use in a charged particle multi-beam assessment tool to detect charged particles from a sample. The detector substrate defines an array of apertures for beam paths of respective charged particle beams of a multi-beam. The detector substrate includes a sensor unit array. A sensor unit of the sensor unit array is adjacent to a corresponding aperture of the aperture array. The sensor unit is configured to capture charged particles from the sample. The detector array may include an amplification circuit associated with each sensor unit in the sensor unit array and proximate to the corresponding aperture in the aperture array. The amplification circuit may include a Trans Impedance Amplifier and/or an analogue to digital converter.

A plasma processing apparatus includes a mounting table, an acquisition unit, a calculation unit, and an elevation control unit. The mounting table mounts thereon a target object as a plasma processing target. The elevation mechanism vertically moves a focus ring surrounding the target object. The acquisition unit acquires state information indicating a measured state of the target object. The calculation unit calculates a height of the focus ring at which positional relation between an upper surface of the target object and an upper surface of the focus ring satisfies a predetermined distance based on the state of the target object that is indicated by the state information acquired by the acquisition unit. The elevation control unit controls the elevation mechanism to vertically move the focus ring to the height calculated by the calculation unit.

A multi-charged particle beam writing apparatus according to one aspect of the present invention includes a region setting unit configured to set, as an irradiation region for a beam array to be used, the region of the central portion of an irradiation region for all of multiple beams of charged particle beams implemented to be emittable by a multiple beam irradiation mechanism, and a writing mechanism, including the multiple beam irradiation mechanism, configured to write a pattern on a target object with the beam array in the region of the central portion having been set in the multiple beams implemented.

A particle beam system includes a multiple beam particle source to generate a multiplicity of charged individual particle beams, and a multi-pole lens sequence with first and second multi-pole lens arrays. The particle beam system also includes a controller to control the multi-pole lenses of the multi-pole lens sequence so related groups of multi-pole lenses of the multi-pole lens sequence through which the same individual particle beam passes in each case altogether exert an individually adjustable and focussing effect on the respective individual particle beam passing therethrough.

Wafer-to-wafer and within-wafer image contrast variations can be identified and mitigated by extracting an image frame during recipe setup and then during runtime at the same location. Image contrast is determined for the two image frames. A ratio of the contrast for the two image frames can be used to determine contrast variations and focus variation.

A multi-charged particle beam writing apparatus according to one aspect of the present invention includes a region setting unit configured to set, as an irradiation region for a beam array to be used, the region of the central portion of an irradiation region for all of multiple beams of charged particle beams implemented to be emittable by a multiple beam irradiation mechanism, and a writing mechanism, including the multiple beam irradiation mechanism, configured to write a pattern on a target object with the beam array in the region of the central portion having been set in the multiple beams implemented.

A charged particle assessment tool including: an objective lens configured to project a plurality of charged particle beams onto a sample, the objective lens having a sample-facing surface defining a plurality of beam apertures through which respective ones of the charged particle beams are emitted toward the sample; and a plurality of capture electrodes, each capture electrode adjacent a respective one of the beam apertures, configured to capture charged particles emitted from the sample.

An object of the invention is to acquire a high-quality image while maintaining an improvement in throughput of image acquisition (measurement (length measurement)). The present disclosure provides a charged particle beam system including a charged particle beam device and a computer system configured to control the charged particle beam device. The charged particle beam device includes an objective lens, a sample stage, and a backscattered electron detector that is disposed between the objective lens and the sample stage and that adjusts a focus of a charged particle beam with which a sample is irradiated. The computer system adjusts a value of an electric field on the sample in accordance with a change in a voltage applied to the backscattered electron detector.

In one embodiment, a charged particle beam writing apparatus includes a positioning deflector adjusting an irradiation position of a charged particle beam radiated to a substrate which is a writing target, a fixed deflector which is disposed downstream of the positioning deflector in a traveling direction of the charged particle beam, and in which an amount of deflection is fixed, a focus correction lens performing focus correction on the charged particle beam according to a surface height of the substrate, and an object lens focusing the charged particle beam.