Patent ID: 9123501
Filing Date: 2015-09-01
Classification: H01J

Abstract:
1. A diffraction aberration correction device comprising: a charged particle gun emitting a charged particle beam; an objective aperture that limits a beam diameter of the charged particle beam; a diffraction aberration corrector in which a first pair of poles of two vector potentials are disposed at positions symmetrical with respect to a beam axis of a charged particle beam having passed through the objective aperture, the first pair of poles inducing a vector potential in a first direction which is perpendicular to the beam axis, the first pair of poles being disposed and configured so as to be rotationally symmetrical with respect to the first direction, and in which a second pair of poles of vector potentials are disposed at positions at which relative angles with respect to the first pair of the two vector potentials are 90°, the second pair of poles inducing a vector potential in a second direction which is perpendicular to the beam axis, the second pair of poles being disposed and configured so as to be rotationally symmetrical with respect to the second direction; an objective lens that focuses the charged particle beam on a sample; a deflector that deflects the charged particle beam; and a detector that detects a secondary particle generated from a sample by irradiation of the charged particle beam.