公开(公告)号：US20190131107A1

公开(公告)日：2019-05-02

申请号：US16089292

申请日：2016-08-22

Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION

Inventor： Hirokazu TAMAKI ,  Ken HARADA ,  Keiji TAMURA ,  Yoshifumi TANIGUCHI ,  Hiroto KASAI ,  Toshie YAGUCHI ,  Takafumi YOTSUJI

IPC: H01J37/26 ,  H01J37/22 ,  H01J37/295

CPC classification number: H01J37/263 ,  H01J37/22 ,  H01J37/226 ,  H01J37/26 ,  H01J37/295

Abstract: An electron microscope for observation by illuminating an electron beam on a specimen, includes: an edge element disposed in a diffraction plane where a direct beam not diffracted by but transmitted through the specimen converges or a plane equivalent to the diffraction plane; and a control unit for controlling the electron beam or the edge element. The edge element includes a blocking portion for blocking the electron beam, and an aperture for allowing the passage of the electron beam. The aperture is defined by an edge of the blocking portion in a manner that the edge surrounds a convergence point of the direct beam in the diffraction plane. The control unit varies contrast of an observation image by shifting, relative to the edge, the convergence point of the direct beam along the edge while maintaining a predetermined distance between the convergence point of the direct beam and the edge.