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:
May. 02, 1995
Filed:
Nov. 27, 1992
Tadashi Otaka, Katsuta, JP;
Akimitsu Okura, Katsuta, JP;
Hiroshi Iwamoto, Ibaraki, JP;
Hideo Todokoro, Tokyo, JP;
Tsutomu Komoda, Tokyo, JP;
Issei Tobita, Mito, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An electron beam apparatus comprises an electron beam source, a unit for irradiating an electron beam on a specimen, a detector for secondary electrons, an electrode for generating an electric field sufficient to draw out secondary electrons in a recess in the specimen from the recess, and a unit for generating a magnetic field for focusing secondary electrons drawn out of the recess. With this construction, the secondary electrons drawn out of the recess by the electric field reach the detector without being attracted by the electrode. By adopting this construction, a contact hole of high aspect ratio formed in a semiconductor device and having a small diameter and a large depth can be observed.