Methods of producing grating materials with variable height are provided. In one example, a method may include providing a grating material atop a substrate, and positioning a shadow mask between the grating material and an ion source, wherein the shadow mask is separated from the grating material by a distance. The method may further include etching the grating material using an ion beam passing through a set of openings of the shadow mask, wherein a first depth of a first portion of the grating material is different than a second depth of a second portion of the grating material.

The invention relates to an exposure apparatus and a method for projecting a charged particle beam onto a target. The exposure apparatus comprises a charged particle optical arrangement comprising a charged particle source for generating a charged particle beam and a charged particle blocking element and/or a current limiting element for blocking at least a part of a charged particle beam from a charged particle source. The charged particle blocking element and the current limiting element comprise a substantially flat substrate provided with an absorbing layer comprising Boron, Carbon or Beryllium. The substrate further preferably comprises one or more apertures for transmitting charged particles. The absorbing layer is arranged spaced apart from the at least one aperture.

A method includes operating a multiple particle beam system at different working points. The numerical aperture can be set for each of the working points in such a way that the resolution of the multiple particle beam system is optimal. In the process, the beam pitch between adjacent individual particle beams on the sample to be scanned is kept constant as a boundary condition. There are no mechanical reconfigurations of the system whatsoever for the purposes of varying the numerical aperture.

A Schottky thermal field emitter (TFE) source integrated with a beam splitter by a standoff, which supports the beam splitter above the Schottky TFE extractor faceplate by a distance of 0.05 mm to 2 mm. The beam splitter includes a microhole array integrated with the standoff and being disposed opposite the extractor faceplate, the microhole array having a plurality of microholes that split the electron beam generated by the Schottky TFE into a plurality of beamlets. The support and extractor may be fabricated from the same material or from different materials. The support may be formed from a high temperature resistive material, which causes a potential difference between the extractor and the microhole array. This potential difference creates positively charged electrostatic lenses at the microholes, which increases current in the individual beamlets. Voltage on the microarray plate may be varied to achieve a high beamlet current.

Arrangements involving objective lens array assemblies for charged-particle assessment tools are disclosed. In one arrangement, the assembly comprises an objective lens array and a control lens array. Each objective lens projects a respective sub-beam of a multi-beam onto a sample. The control lens array is associated with the objective lens array and positioned up-beam of the objective lens array. The control lenses pre-focus the sub-beams.

A charged particle beam pattern forming device is described, a charged particle beam passing through a third aperture for forming a charged particle beam pattern, the charged particle beam pattern forming device including: a first element including a first aperture, a second element including a second aperture, the second aperture overlapping the first aperture, wherein the third aperture is defined by an overlap of the first aperture and the second aperture, and a shape of the third aperture is capable of being changed by a driver such that the first element is moved in a first direction and the second element is moved in a second direction opposite to the first direction.

A pattern inspection apparatus according to an aspect described herein includes: a stage on which an object to be inspected is capable to be mounted, a multibeam column that irradiates the object to be inspected with multi-primary electron beams, and a multi-detector including a first detection pixel that receives irradiation of a first secondary electron beam emitted after a first beam scanning region of the object to be inspected is irradiated with a first primary electron beam of the multi-primary electron beams and a second detection pixel that receives irradiation of a second secondary electron beam emitted after a second beam scanning region adjacent to the first beam scanning region of the object to be inspected and overlapping with the first beam scanning region is irradiated with a second primary electron beam adjacent to the first primary electron beam of the multi-primary electron beams; a comparison unit that obtains a difference in beam intensity between the first primary electron beam and the second primary electron beam by comparing overlapping portions of a first frame image acquired through entering of the first secondary electron beam into the first detection pixel and a second frame image acquired through entering of the second secondary electron beam into the second detection pixel; and a sensitivity adjustor that adjusts detection sensitivity of the first detection pixel and/or the second detection pixel so as to correct the difference in beam intensity.

The present technology encompasses plasma sources including a first plate defining a first plurality of apertures arranged in a first set of rows. The first plate may include a first set of electrodes extending along a separate row of the first set of rows. The plasma sources may include a second plate defining a second plurality of apertures arranged in a second set of rows. The second plate may include a second set of electrodes extending along a separate row of the second set of rows. Each aperture of the second plurality of apertures may be axially aligned with an aperture of the first plurality of apertures. The plasma sources may include a third plate positioned between the first plate and the second plate. The third plate may define a third plurality of apertures.

A multi-beam inspection apparatus including an improved source conversion unit is disclosed. The improved source conversion unit may comprise a micro-structure deflector array including a plurality of multipole structures. The micro-deflector deflector array may comprise a first multipole structure having a first radial shift from a central axis of the array and a second multipole structure having a second radial shift from the central axis of the array. The first radial shift is larger than the second radial shift, and the first multipole structure comprises a greater number of pole electrodes than the second multipole structure to reduce deflection aberrations when the plurality of multipole structures deflects a plurality of charged particle beams.

A transmission electron microscope includes a control unit for: acquiring an image of an objective aperture; obtaining a position of the objective aperture; obtaining an amount of deviation between an object position and the position of the objective aperture, based on the position of the objective aperture; and operating an aperture moving mechanism, based on the amount of deviation of the position of the objective aperture. The position of the objective aperture is obtained by: binarizing the image of the objective aperture by using a set threshold; obtaining an area of an aperture hole of the objective aperture from the binarized image; determining whether the area is within a predetermined range; changing the threshold when a determination is made that the area is outside the predetermined range; and obtaining a position of the objective aperture when a determination is made that the area is within the predetermined range.