公开(公告)号：US10535497B2

公开(公告)日：2020-01-14

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 ,  H01J37/295 ,  H01J37/22

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.

公开(公告)号：US09715991B2

公开(公告)日：2017-07-25

申请号：US15125989

申请日：2014-04-04

Applicant: Hitachi High-Technologies Corporation

Inventor： Yoichi Hirayama ,  Hirokazu Tamaki

IPC: H01J37/153 ,  H01J37/14 ,  H01J37/26

CPC classification number: H01J37/153 ,  H01J37/14 ,  H01J37/26 ,  H01J2237/1534 ,  H01J2237/2802

Abstract: In general, in a multipole lens of an aberration corrector of a charged particle beam device, there is only one condition that can be set where both a spherical aberration correction condition and magnetic saturation are satisfied. Therefore, a plurality of acceleration voltages cannot be handled. Consequently, the present invention provides a spherical aberration corrector that satisfies the magnetic saturation state for a plurality of aberration correction conditions by selectively magnetizing a plurality of pole groups of the multipole lens according to the changes in the objective lens magnetization current.