Patent ID: 8258475
Filing Date: 2012-09-04
Classification: H01J

Abstract:
1. A charged particle radiation device comprising: a charged particle optical system including an aberration corrector; a control means of the charged particle optical system; and an information processing unit, wherein the information processing unit generates an aberration correction signal of the aberration corrector to be outputted, captures a plurality of images by causing a beam to scan over a specimen, both a tilt angle and an azimuth angle of the beam being varied, measures an astigmatic difference, an angle, and defocus with respect to the plurality of the images captured, evaluates an aberration amount from these values, and feeds back the evaluated aberration amount to a correction signal amount of the aberration corrector and a control amount of the control means at the time of the next evaluation, respectively, thereby repeats the aberration correction until the evaluated aberration amount reaches a preset target value.