The present invention relates to a scanning electron microscope configured to scan a workpiece, such as a wafer, mask, panel, or substrate, with an electron beam to generate an image of the workpiece. The scanning electron microscope includes a deflector (17, 18) configured to deflect the electron beam to scan a target region (T) on the workpiece (W) with the electron beam, and a deflection controller (22) configured to apply to the deflectors (17, 18) a scanning voltage that causes the electron beam to scan the target region (T) and an offset voltage that shifts the electron beam from an optical axial center (O) to the target region (T).

Provided is a charged particle beam device capable of focusing with high accuracy even when a charged particle beam has a large off-axis amount. The charged particle beam device generates an observation image of a sample by irradiating the sample with a charged particle beam, and includes: a deflection unit that inclines the charged particle beam; a focusing lens that focuses the charged particle beam; an adjustment unit that adjusts a lens strength of the focusing lens based on an evaluation value calculated from the observation image; a storage unit that stores a relationship between a visual field movement amount and the lens strength; and a filter setting unit that calculates the visual field movement amount based on an inclination angle of the charged particle beam and the relationship, and sets an image filter to be superimposed on the observation image based on the calculated visual field movement amount.

Provided is a charged particle beam device capable of focusing with high accuracy even when a charged particle beam has a large off-axis amount. The charged particle beam device generates an observation image of a sample by irradiating the sample with a charged particle beam, and includes: a deflection unit that inclines the charged particle beam; a focusing lens that focuses the charged particle beam; an adjustment unit that adjusts a lens strength of the focusing lens based on an evaluation value calculated from the observation image; a storage unit that stores a relationship between a visual field movement amount and the lens strength; and a filter setting unit that calculates the visual field movement amount based on an inclination angle of the charged particle beam and the relationship, and sets an image filter to be superimposed on the observation image based on the calculated visual field movement amount.

There is provided a technique capable of shortening a photographing time and obtaining a more accurate photographed image when photographing a sample SAM using a charged particle beam device 1. The charged particle beam device 1 includes an electron gun 3, an objective lens 6, a stage 8, detectors 10 and 11, an integrated control unit C0, a photographing function, and an autofocus function. Each of a plurality of photographing visual fields is focused in a focus value calculation visual field 64 adjacent to a designated visual field 61 designated as a photographing target among the plurality of photographing visual fields, and a focus value calculated in the focus value calculation visual field 64 is used for calculating focus values of each of the plurality of photographing visual fields.

There is provided a technique capable of shortening a photographing time and obtaining a more accurate photographed image when photographing a sample SAM using a charged particle beam device 1. The charged particle beam device 1 includes an electron gun 3, an objective lens 6, a stage 8, detectors 10 and 11, an integrated control unit C0, a photographing function, and an autofocus function. Each of a plurality of photographing visual fields is focused in a focus value calculation visual field 64 adjacent to a designated visual field 61 designated as a photographing target among the plurality of photographing visual fields, and a focus value calculated in the focus value calculation visual field 64 is used for calculating focus values of each of the plurality of photographing visual fields.

An electron-beam device includes upper-column electron optics and lower-column electron optics. The upper-column electron optics include an aperture array to divide an electron beam into a plurality of electron beamlets. The upper-column electron optics also include a lens array with a plurality of lenses to adjust the focus of the plurality of electron beamlets. Respective lenses of the plurality of lenses are to adjust the focus of respective electron beamlets of the plurality of electron beamlets. The upper-column electron optics further include a first global lens to adjust the focus of the plurality of electron beamlets in a manner opposite to the lens array.

An electron-beam device includes upper-column electron optics and lower-column electron optics. The upper-column electron optics include an aperture array to divide an electron beam into a plurality of electron beamlets. The upper-column electron optics also include a lens array with a plurality of lenses to adjust the focus of the plurality of electron beamlets. Respective lenses of the plurality of lenses are to adjust the focus of respective electron beamlets of the plurality of electron beamlets. The upper-column electron optics further include a first global lens to adjust the focus of the plurality of electron beamlets in a manner opposite to the lens array.

An improved charged particle beam inspection apparatus, and more particularly, a particle beam inspection apparatus for detecting a thin device structure defect is disclosed. An improved charged particle beam inspection apparatus may include a charged particle beam source to direct charged particles to a location of a wafer under inspection over a time sequence. The improved charged particle beam apparatus may further include a controller configured to sample multiple images of the area of the wafer at difference times over the time sequence. The multiple images may be compared to detect a voltage contrast difference or changes to identify a thin device structure defect.

An improved charged particle beam inspection apparatus, and more particularly, a particle beam inspection apparatus for detecting a thin device structure defect is disclosed. An improved charged particle beam inspection apparatus may include a charged particle beam source to direct charged particles to a location of a wafer under inspection over a time sequence. The improved charged particle beam apparatus may further include a controller configured to sample multiple images of the area of the wafer at difference times over the time sequence. The multiple images may be compared to detect a voltage contrast difference or changes to identify a thin device structure defect.

The present invention relates to a method for measuring a sample with a microscope, the method comprising scanning the sample using a focusing plane having a first angle with respect to a top surface of the sample and computing a confidence distance based on the first angle. The method further comprises selecting at least one among a plurality of alignment markers on the sample for performing a lateral alignment of the scanning step and/or for performing a lateral alignment of an output of the scanning step. In particular, the at least one alignment marker selected at the selecting step is chosen among the alignment markers placed within the confidence distance from an intersection of the focusing plane with the top surface.