CHARGED PARTICLE BEAM MICROSCOPE WITH DIFFRACTION ABERRATION CORRECTOR APPLIED THERETO

摘要

Based on the operation principle of diffraction aberration correction for controlling the phase of the electron beam using the Aharonov-Bohm effect, a diffraction aberration corrector is formed by the structure of a corrector formed by the multipole of the solenoid coil ring and a function of adjusting the degree of orthogonality or axial shift of the vector potential with respect to the beam axis. In order to cause a phase difference, the diffraction aberration corrector that induces a vector potential, which is perpendicular to the beam axis and has a symmetrical distribution within the orthogonal plane with respect to the beam axis, is provided near the objective aperture and the objective lens. A diffracted wave traveling in a state of being inclined from the beam axis passes through the ring of the magnetic flux. Therefore, since the phase difference within the beam diameter is increased by the Aharonov-Bohm effect due to the vector potential, it is possible to suppress the intensity of the electron beam on the sample.