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:
Nov. 29, 2011
Filed:
Jul. 24, 2006
Mamoru Nakasuji, Tokyo, JP;
Takeshi Murakami, Tokyo, JP;
Tohru Satake, Tokyo, JP;
Tsutomi Karimata, Tokyo, JP;
Toshifumi Kimba, Tokyo, JP;
Matsutaro Miyamoto, Tokyo, JP;
Hiroshi Sobukawa, Tokyo, JP;
Satoshi Mori, Tokyo, JP;
Yuichiro Yamazaki, Tokyo, JP;
Ichirota Nagahama, Tokyo, JP;
Mamoru Nakasuji, Tokyo, JP;
Takeshi Murakami, Tokyo, JP;
Tohru Satake, Tokyo, JP;
Tsutomi Karimata, Tokyo, JP;
Toshifumi Kimba, Tokyo, JP;
Matsutaro Miyamoto, Tokyo, JP;
Hiroshi Sobukawa, Tokyo, JP;
Satoshi Mori, Tokyo, JP;
Yuichiro Yamazaki, Tokyo, JP;
Ichirota Nagahama, Tokyo, JP;
Ebara Corporation, Tokyo, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
An electron beam emitted from an electron gun (G) forms a reduced image on a sample (S) through a non-dispersion Wien-filter (-), an electromagnetic deflector (-), a beam separator (-), and a tablet lens (-) as an objective lens. The beam separator (-) is configured such that a distance by which a secondary electron beam passes through the beam separator is approximately three times longer than a distance by which a primary electron beam passes through the beam separator. Therefore, even if a magnetic field in the beam separator is set to deflect the primary electron beam by a small angle equal to or less than approximately 10 degrees, the secondary electron beam can be deflected by approximately 30 degrees, so that the primary and secondary electron beams are sufficiently separated. Also, since the primary electron beam is deflected by a small angle, less aberration occurs in the primary electron beam. Accordingly, since a light path length of a primary electro-optical system, it is possible to reduce the influence of space charge and the occurrence of deflection aberration.