Patent ID: 8280664

Claim:
An electron beam apparatus for inspecting a pattern on a sample using an electron beam, comprising: first processing means for calculating a coordinate error (Δx,Δy) of a measured XY coordinate (x,y) of each of arbitrary reference points on the sample from a calculated ideal position XY coordinate of the reference point; second processing means for calculating an orthogonal error of the XY coordinates based on the calculated coordinate errors; third processing means for calculating an error due to mirror distortion of an interferometer of the electron beam apparatus on the basis of the calculated coordinate errors; orthogonal error correcting means for compensating the measured XY coordinates (x,y) on the basis of the calculated orthogonal error upon inspecting the sample; and beam deflection correcting means for compensating deflection by a beam deflector disposed in a second electro-optical system on the basis of the calculated mirror distortion error upon inspecting the sample.