Patent ID: 7923701

Claim:
Charged particle beam equipment comprising: a charged particle beam source for generating a charged particle beam; a specimen stand for holding a specimen having a non-periodic structure; a lens system for converging the charged particle beam onto the specimen; a scanner for scanning the charged particle beam on the specimen; a deflector for deflecting the charged particle beam; a detector for detecting specimen signal generated from the specimen by irradiation of the charged particle beam; an image processor for carrying out image calculation; a display for displaying the specimen image; and a controller comprising a computer readable medium containing instructions that, when executed, cause the charged particle beam equipment to perform operations including: calculating a magnification error of a first magnification by extracting periodic dimension by the image processor out of an enlarged image of a specimen having known periodical structure recorded at the first magnification; recording the enlarged image of the specimen having non-periodic structure as a reference image at the first magnification of which magnification error is corrected; recording the enlarged image of the specimen having non-periodic structure as an evaluation image after visual field is moved by controlling the deflector; obtaining ratio between control amount of the deflector and visual field moving amount out of visual field moving amount of the evaluation image corresponding to the reference image measured by the image processor; setting magnification into a second magnification different from the first magnification; obtaining visual field moving amount of enlarged image of a non-periodical structure specimen before and after the visual field movement by controlling the deflector in the second magnification; carrying out correction of magnification of the second magnification from the ratio between visual field moving amount at the second magnification and visual field movement amount at the first magnification of which magnification error is corrected; and using specimen of which periodical structure is artificially formed as a specimen including a known periodical structure.