Patent ID: 8704175
Filing Date: 2014-04-22
Classification: H01J

Abstract:
1. A scanning electron microscope that irradiates an electron beam emitted from an electron source onto a sample and acquires a sample image based on secondary electrons and reflective electrons generated from the sample, comprising: a tilt deflector arranged inside an electron beam column and for tilting the electron beam; an astigmatism corrector arranged inside the electron beam column and capable of correcting astigmatism of the electron beam; an objective lens that converges the electron beam and irradiates the electron beam onto the sample; and a control unit that controls the tilt deflector and the astigmatism corrector, wherein the control unit measures astigmatism of the electron beam from the electron source to the sample inside the electron beam column by a first astigmatism measuring method, and measures astigmatism of the electron beam occurring from the objective lens to surroundings of the sample by a second astigmatism measuring method.