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.

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.

Disclosed herein are techniques directed toward a protective shutter for a charged particle microscope. An example apparatus at least includes a charged particle column and a focused ion beam (FIB) column, a gas injection nozzle coupled to a translation device, the translation device configured to insert the gas injection nozzle in close proximity to a stage, and a shutter coupled to the gas injection nozzle and arranged to be disposed between the sample and the SEM column when the gas injection nozzle is inserted in close proximity to the stage.

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.

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.

Disclosed herein is an electron-optical assembly testing system for testing an electron-optical assembly, the system comprising: a source of charged particles configured to emit a beam of charged particles; an electron-optical assembly holder configured to hold an electron-optical assembly to be tested such that, when the system is in use with an electron-optical assembly held by the electron-optical assembly holder, the electron-optical assembly is illuminated by the beam; and a sub-beam detector for detecting sub-beams of charged particles that have been transmitted through the electron-optical assembly.

Certain improvements of multi-beam raster units such as multi-beam generating units and multi-beam deflector units of a multi-beam charged particle microscopes are provided. The improvements include design, fabrication and adjustment of multi-beam raster units including apertures of specific shape and dimensions. The improvements can enable multi-beam generation and multi-beam deflection or stigmation with higher precision. The improvements can be relevant for routine applications of multi-beam charged particle microscopes, for example in semiconductor inspection and review, where high reliability and high reproducibility and low machine-to-machine deviations are desirable.

Certain improvements of multi-beam raster units such as multi-beam generating units and multi-beam deflector units of a multi-beam charged particle microscopes are provided. The improvements include design, fabrication and adjustment of multi-beam raster units including apertures of specific shape and dimensions. The improvements can enable multi-beam generation and multi-beam deflection or stigmation with higher precision. The improvements can be relevant for routine applications of multi-beam charged particle microscopes, for example in semiconductor inspection and review, where high reliability and high reproducibility and low machine-to-machine deviations are desirable.

A specimen machining device for machining a specimen by irradiating the specimen with an ion beam includes an ion source for irradiating the specimen with the ion beam, a shielding member disposed on the specimen to block the ion beam, a specimen stage for holding the specimen, a camera for photographing the specimen, a coaxial illumination device for irradiating the specimen with illumination light along an optical axis of the camera, and a processing unit for determining whether to terminate the machining based on an image photographed by the camera. The processing unit performs processing for acquiring information indicating a target machined width, processing for acquiring the image, processing for measuring a machined width on the acquired image, and processing for terminating the machining when the measured machined width equals or exceeds the target machined width.

A specimen machining device for machining a specimen by irradiating the specimen with an ion beam includes an ion source for irradiating the specimen with the ion beam, a shielding member disposed on the specimen to block the ion beam, a specimen stage for holding the specimen, a camera for photographing the specimen, a coaxial illumination device for irradiating the specimen with illumination light along an optical axis of the camera, and a processing unit for determining whether to terminate the machining based on an image photographed by the camera. The processing unit performs processing for acquiring information indicating a target machined width, processing for acquiring the image, processing for measuring a machined width on the acquired image, and processing for terminating the machining when the measured machined width equals or exceeds the target machined width.