The disclosure relates to a method of determining an energy width of a charged particle beam, comprising the steps of providing a charged particle beam, directing said beam towards a specimen, and forming an energy-dispersed beam from a flux of charged particles transmitted through the specimen. As defined herein, the method comprises the steps of providing a slit element in a slit plane, and using said slit element for blocking a part of said energy-dispersed beam, as well as the step of modifying said energy-dispersed beam at the location of said slit plane in such a way that said energy dispersed beam is partially blocked at said slit element. The unblocked part of said energy-dispersed beam is imaged and an intensity gradient of said imaged energy-dispersed beam is determined, with which the energy width of the charged particle beam can be determined.

The present disclosure is related to a Schottky thermal field (TFE) source for emitting an electron beam. Electron optics can adjust a shape of the electron beam before the electron beam impacts a scintillator screen. Thereafter, the scintillator screen generates an emission image in the form of light. An emission image can be adjusted and captured by a camera sensor in a camera at a desired magnification to create a final image of the Schottky TFE source's tip. The final image can be displayed and analyzed to for defects.

An image conversion unit includes a selector and a plurality of image converters. Each image converter is formed from an estimator of machine learning type, and estimates, based on an image acquired under a first observation condition and as a reference image, an image which is presumed to be acquired under a second observation condition. When a particular reference image is selected from among a plurality of reference images displayed on a display, a second observation condition corresponding to the selected reference image is set in an observation mechanism as a next observation condition.

An electron gun includes a cathode that is heated to emit thermions; a cathode heating power supply that supplies a cathode heating current for heating the cathode; a grid that has a first aperture formed therein and that has a grid voltage applied thereto, the grid voltage having a potential lower than that of the cathode, wherein the grid converges the thermions passing through the first aperture by the grid voltage; an anode that has a second aperture formed therein and that has an anode voltage applied thereto, wherein the anode causes the thermions extracted from the cathode to pass through the second aperture as an electron beam by the anode voltage; an anode-voltage power supply that applies the anode voltage to the anode; and a controller that causes the anode voltage having a positive potential to be applied from the anode-voltage power supply to the anode.

There is provided a method of aberration measurement capable of reducing the effects of image drift. The novel method of aberration measurement is for use in an electron microscope. The method comprises the steps of: acquiring a first image that is a TEM (transmission electron microscope) image of a sample; scanning the illumination angle of an electron beam impinging on the sample and acquiring a second image by multiple exposure of a plurality of TEM images generated at different illumination angles; and calculating aberrations from the first and second images.

A method for evaluating a secondary optical system of an electron beam inspection device provided with a primary optical system that irradiates a sample placed at an observation target position with an electron beam emitted from an electron source, and the secondary optical system that forms, on a detector, an enlarged image of an electron beam generated from the sample or an electron beam transmitted through the sample. The method includes: placing a photoelectric surface at the observation target position; irradiating the photoelectric surface with laser; forming an enlarged image of an electron beam generated from the photoelectric surface on the detector by the secondary optical system; and evaluating the secondary optical system based on an electron beam image obtained by the detector.

Systems and methods for tuning and/or calibrating a charged particle beam apparatus are disclosed. According to certain embodiments, a reference specimen comprises a substrate having a plurality of first objects at a first pitch, and a plurality of second objects at a second pitch. Regions containing the first and second objects may overlap. A method of tuning and/or calibrating may comprise analyzing an image of a sample at a plurality of coarseness levels, determining whether a parameter of the image satisfies a criteria based on measured characteristics of the image at the coarseness levels, and adjusting the parameter.

An aberration measurement method for an objective lens in an electron microscope including an objective lens which focuses an electron beam that illuminates a specimen, and a detector which detects an electron beam having passed through the specimen, includes: introducing a coma aberration to the objective lens; measuring an aberration of the objective lens before introducing the coma aberration to the objective lens; measuring an aberration of the objective lens after introducing the coma aberration to the objective lens; and obtaining a position of an optical axis of the objective lens on a detector plane of the detector based on measurement results of the aberration of the objective lens before and after introducing the coma aberration.

The disclosed technology relates to a method and apparatus for correctly positioning a probe suitable for scanning probe microscopy (SPM). The probe is positioned relative to the apex region of a needle-shaped sample, such as a sample for atom probe tomography, in order to perform a SPM acquisition of the apex region to obtain an image of the region. In one aspect, the positioning takes place by an iterative process, starting from a position wherein one side plane of the pyramid-shaped SPM probe interacts with the sample tip. By controlled consecutive scans in two orthogonal directions, the SPM probe tip approaches and finally reaches a position wherein a tip area of the probe interacts with the sample tip's apex region.

An electron microscope includes: an optical system including an aberration correction device; and a control unit that controls the aberration correction device, wherein the control unit performs: processing for displaying, on a display unit, an image for designating a direction of aberration in superposition on an aberration pattern representing a state of aberration, processing for specifying the direction of aberration from the image that has been subjected to a rotation operation, and processing for controlling the aberration correction device to cause the aberration correction device to introduce an aberration in the specified direction.