The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 18, 2022
Filed:
Sep. 07, 2017
Hitachi High-tech Corporation, Tokyo, JP;
Soichiro Matsunaga, Tokyo, JP;
Yasunari Sohda, Tokyo, JP;
Souichi Katagiri, Tokyo, JP;
Makoto Sakakibara, Tokyo, JP;
Hajime Kawano, Tokyo, JP;
Takashi Doi, Tokyo, JP;
HITACHI HIGH-TECH CORPORATION, Tokyo, JP;
Abstract
In order to provide an electron gun capable of maintaining a small spot diameter of a beam converged on a sample even when a probe current applied to the sample is increased, a magnetic field generation sourceis provided with respect to an electron gun including: an electron source; an extraction electrodeconfigured to extract electrons from the electron source; an acceleration electrodeconfigured to accelerate the electrons extracted from the electron source; and a first coiland a first magnetic pathhaving an opening on an electron source side, the first coiland the first magnetic pathforming a control lens configured to converge an electron beam emitted from the acceleration electrode. The magnetic field generation source is provided for canceling a magnetic field, at an installation position of the electron source, generated by the first coiland the first magnetic path