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:
Oct. 30, 2001
Filed:
Feb. 22, 1999
Hideo Todokoro, Nishitama-gun, JP;
Tohru Ishitani, Sayama, JP;
Yasutsugu Usami, Toshima-ku, JP;
Shunroku Taya, Mito, JP;
Hiroyuki Shinada, Chofu, JP;
Taku Ninomiya, Hitachinaka, JP;
Tsuyoshi Ohnishi, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An irradiation electron beam emitted from an electron gun is deflected by an energy filter, and passes through a first projective lens and an objective lens, and then irradiated onto a sample to produce secondary electrons. The secondary electron beam accelerated by a negative voltage applied to the sample passes through the objective lens and the first projective lens, and deflected by the energy filter to be energy dispersed. Only the secondary electrons having a specified energy pass through energy selecting aperture, and further pass through a second projective lens to form a projected image of the secondary electrons on an imager. Such an electron-optical system may be used for dimension evaluation or inspection of semiconductor substrates.